ACT High Frequency Words: 200+ Must-Know Words with Meanings & Practice

Abate verb

Short meaning: to become less strong, reduce, or decrease.

Common in news, reports, and ACT reading passages.

Synonyms: decrease lessen diminish subside

Antonyms: increase intensify expand rise

Example: "The storm finally began to abate, allowing residents to return to their homes safely."

Abdicate verb

Short meaning: to give up power, authority, or responsibility.

Often used when leaders step down or withdraw from duty.

Synonyms: resign step down give up relinquish

Antonyms: assume take on accept claim

Example: "The king chose to abdicate his throne, leaving his son to take responsibility for the kingdom."

Aberration noun

Short meaning: something unusual or unexpected, a deviation from what is normal.

ACT uses it to describe unexpected results, behaviors, or events.

Synonyms: anomaly irregularity deviation outlier

Antonyms: normality regularity consistency conformity

Example: "The sudden rise in winter temperatures was an aberration that surprised scientists."

Abstain verb

Short meaning: to choose not to do something, especially something tempting or habitual.

Common in academic passages when discussing choices, discipline, or decision-making.

Synonyms: refrain hold back avoid withhold

Antonyms: indulge participate engage partake

Example: "To focus on her studies, Maria decided to abstain from social media for an entire week."

Accentuate verb

Short meaning: to make something more noticeable or emphasize it.

Often used in literature and analysis to show how writers highlight key ideas or emotions.

Synonyms: emphasize highlight underline draw attention to

Antonyms: downplay minimize diminish reduce

Example: "The author uses vivid imagery to accentuate the character’s growing sense of fear."

Acclaim verb / noun

Short meaning: to praise someone publicly; enthusiastic approval.

Appears in reviews, biographies, and articles discussing achievement or recognition.

Synonyms: praise applaud commend celebrate

Antonyms: criticize disapprove condemn dismiss

Example: "The young scientist received national acclaim for her groundbreaking research."

Accolade noun

Short meaning: an award, honor, or strong expression of praise.

Common in articles and biographies describing achievements or recognition.

Synonyms: award honor praise distinction

Antonyms: criticism disapproval blame rebuke

Example: "Winning the national art competition was a significant accolade that boosted her confidence."

Accord noun / verb

Short meaning: as a noun — agreement or harmony; as a verb — to give or grant something.

Appears in ACT passages discussing agreements, peaceful resolutions, or when someone is granted respect or rights.

Synonyms: agreement harmony grant bestow

Antonyms: disagreement conflict withhold deny

Example: "The two groups finally reached an accord after hours of negotiation, agreeing to share resources fairly."

Acquiesce verb

Short meaning: to accept or agree to something quietly, often without protest.

Seen in ACT passages where characters yield, comply, or go along with a decision.

Synonyms: agree comply consent go along

Antonyms: resist oppose refuse protest

Example: "Although he disagreed with the plan, Daniel eventually acquiesced to avoid further conflict."

Acrimony noun

Short meaning: bitter feelings, sharp hostility, or harshness in speech or behavior.

Appears in ACT passages describing tense relationships, conflicts, or emotional confrontations.

Synonyms: bitterness hostility resentment ill will

Antonyms: friendliness kindness harmony goodwill

Example: "The acrimony between the two candidates was evident in every debate they shared."

Adept adjective

Short meaning: highly skilled or very good at doing something.

Frequently used in ACT passages to describe someone's talent, proficiency, or natural ability.

Synonyms: skilled proficient capable expert

Antonyms: unskilled inexperienced inept clumsy

Example: "Jenna is so adept at solving complex equations that her classmates often ask her for help."

Admonish verb

Short meaning: to warn or gently criticize someone for their behavior.

Appears in ACT narratives when a character receives guidance, correction, or a soft warning.

Synonyms: warn scold caution reprove

Antonyms: praise encourage approve commend

Example: "The teacher had to admonish Leo for repeatedly whispering during the exam."

Adversarial adjective

Short meaning: involving conflict, opposition, or hostility.

Often seen in ACT passages discussing debates, competition, or tense relationships.

Synonyms: hostile opposing antagonistic competitive

Antonyms: cooperative friendly supportive harmonious

Example: "The discussion became increasingly adversarial as both sides refused to compromise."

Adversity noun

Short meaning: difficulty, hardship, or misfortune.

Very common in ACT passages that describe challenges, obstacles, or personal growth.

Synonyms: hardship difficulty struggle misfortune

Antonyms: prosperity success advantage fortune

Example: "Despite facing significant adversity, the team remained determined to finish the project."

Aesthetic adjective / noun

Short meaning: related to beauty, artistic taste, or visual appeal.

Frequently used in ACT reading passages about art, design, literature, and creative expression.

Synonyms: artistic beautiful visual tasteful

Antonyms: unattractive plain unaesthetic distasteful

Example: "The designer’s minimalist aesthetic appealed to clients who preferred clean and simple spaces."

Aestheticize verb

Short meaning: to make something appear more beautiful or artistic.

Often used in literary and cultural analysis when discussing how writers or artists beautify ideas, scenes, or objects.

Synonyms: beautify romanticize idealize embellish

Antonyms: devalue simplify criticize downplay

Example: "The filmmaker chose to aestheticize the conflict, using soft colors and poetic imagery to portray a harsh reality."

Affluent adjective

Short meaning: having a lot of money; wealthy.

Common in ACT passages describing social classes, economic differences, or privileged lifestyles.

Synonyms: wealthy prosperous well-off rich

Antonyms: poor impoverished needy destitute

Example: "Growing up in an affluent neighborhood gave her access to resources many students could only dream of."

Agnostic noun / adjective

Short meaning: someone who believes that the existence of God or the truth about ultimate reality is unknown or unknowable.

Often appears in ACT passages discussing philosophy, belief systems, or differing viewpoints.

Synonyms: doubter skeptic questioner noncommittal thinker

Antonyms: believer theist certain convinced

Example: "Although he was raised in a religious home, Josh identified as agnostic because he felt there wasn’t enough evidence to choose one belief over another."

Aloof adjective

Short meaning: emotionally distant, uninvolved, or not friendly.

Often appears in ACT narratives to describe characters who are detached, reserved, or hard to read.

Synonyms: distant detached reserved unapproachable

Antonyms: friendly warm sociable approachable

Example: "Despite joining the group, Maya remained aloof, speaking only when someone asked her a direct question."

Altruistic adjective

Short meaning: showing selfless concern for the well-being of others.

Common in ACT passages discussing moral choices, generosity, or characters who help others without expecting anything in return.

Synonyms: selfless charitable compassionate generous

Antonyms: selfish greedy self-centered uncaring

Example: "Her altruistic decision to donate most of her winnings surprised everyone at the ceremony."

Ambiguous adjective

Short meaning: unclear or open to more than one interpretation.

Frequently appears in ACT reading when discussing unclear statements, confusing ideas, or multiple possible meanings.

Synonyms: unclear vague uncertain equivocal

Antonyms: clear definite unambiguous explicit

Example: "The instructions were so ambiguous that no one was sure how to begin the experiment."

Ambivalent adjective

Short meaning: having mixed or conflicting feelings about something.

Common in ACT passages where characters feel torn, uncertain, or emotionally conflicted about a decision or situation.

Synonyms: uncertain conflicted torn unsure

Antonyms: certain decisive clear-cut resolved

Example: "She felt ambivalent about moving to a new city—excited for new opportunities but nervous about leaving home."

Amicable adjective

Short meaning: friendly and peaceful; showing goodwill rather than conflict.

Common in ACT passages describing relationships, negotiations, or resolutions handled with kindness and cooperation.

Synonyms: friendly peaceful cordial cooperative

Antonyms: hostile unfriendly antagonistic aggressive

Example: "Even after their disagreement, the two remained amicable and continued to work together effectively."

Anecdote noun

Short meaning: a short, interesting, or amusing story about a real incident or person.

Common in ACT passages, especially when authors use personal stories to illustrate a point or engage the reader.

Synonyms: story tale narrative account

Antonyms: analysis theory generalization data

Example: "The speaker opened her presentation with a humorous anecdote that immediately captured the audience’s attention."

Animosity noun

Short meaning: strong hostility or deep-seated dislike.

Frequently appears in ACT passages describing tension, long-standing conflicts, or emotional resentment between characters or groups.

Synonyms: hostility resentment ill will antagonism

Antonyms: friendliness goodwill harmony affection

Example: "Years of rivalry had created such animosity between the teams that even casual games became tense."

Anomaly noun

Short meaning: something unusual, unexpected, or different from what is standard.

Frequently appears in ACT science and reading passages when describing rare events, unexpected results, or anything that breaks a pattern.

Synonyms: irregularity abnormality oddity outlier

Antonyms: normality regularity conformity consistency

Example: "The scientist noted an anomaly in the data, which suggested the experiment needed to be repeated."

Antagonize verb

Short meaning: to make someone angry or hostile; to provoke conflict.

Common in ACT passages describing behavior that escalates tension, creates conflict, or provokes negative reactions.

Synonyms: provoke irritate anger annoy

Antonyms: soothe calm please comfort

Example: "His constant teasing only served to antagonize his classmates, making group work more difficult."

Apathy noun

Short meaning: lack of interest, enthusiasm, or concern.

Often appears in ACT passages to describe emotional disengagement, lack of motivation, or characters who simply do not care about a situation.

Synonyms: indifference unconcern disinterest detachment

Antonyms: enthusiasm interest passion concern

Example: "The student's apathy toward the assignment was clear when he turned in a nearly blank page."

Apprehensive adjective

Short meaning: worried, uneasy, or fearful about something that might happen.

Frequently used in ACT narratives to describe characters who feel nervous or uncertain before an important event or decision.

Synonyms: anxious uneasy nervous fearful

Antonyms: confident calm assured fearless

Example: "Maya felt apprehensive before the interview, unsure of how the panel would react to her answers."

Archaic adjective

Short meaning: very old or outdated; no longer in common use.

Common in ACT literature and history passages describing old language, ancient customs, or outdated technologies.

Synonyms: old-fashioned outdated antique obsolete

Antonyms: modern current contemporary up-to-date

Example: "The author intentionally used archaic phrases to give the story a historical and poetic feel."

Arduous adjective

Short meaning: extremely difficult, requiring great effort or hard work.

Common in ACT passages that describe challenging journeys, demanding tasks, or situations requiring persistence.

Synonyms: difficult strenuous challenging laborious

Antonyms: easy effortless simple manageable

Example: "Finishing the marathon was an arduous task, but the runners felt proud of their determination."

Arid adjective

Short meaning: extremely dry; lacking moisture; also used to describe something dull or lifeless.

Frequently appears in ACT science and reading passages describing deserts, dry climates, or boring/unenjoyable writing or discussions.

Synonyms: dry parched barren lifeless

Antonyms: moist fertile lush vibrant

Example: "The hikers struggled to find water in the arid landscape that stretched for miles."

Articulate verb / adjective

Short meaning: as a verb — to clearly express ideas or feelings; as an adjective — able to speak or express oneself clearly and effectively.

Common in ACT reading passages describing communication skills, strong speakers, or characters who express ideas with clarity.

Synonyms: express communicate eloquent clear-spoken

Antonyms: mumble incoherent unclear tongue-tied

Example: "The student delivered an articulate presentation that impressed both classmates and teachers."

Ascertain verb

Short meaning: to find out or discover something with certainty.

Common in ACT reading and science passages when characters or researchers verify facts, confirm information, or seek accurate answers.

Synonyms: determine discover verify confirm

Antonyms: assume guess misinterpret doubt

Example: "The detective worked tirelessly to ascertain the truth behind the mysterious disappearance."

Assert verb

Short meaning: to state something confidently and firmly.

Common in ACT reading passages when authors or characters express strong opinions, claims, or beliefs.

Synonyms: declare claim maintain affirm

Antonyms: deny question doubt withdraw

Example: "The author asserts that creativity is just as important as logic in solving complex problems."

Assiduous adjective

Short meaning: showing great care, attention, and persistent effort.

Often appears in ACT passages describing hardworking characters, detailed research, or consistent dedication to a task.

Synonyms: diligent persistent dedicated meticulous

Antonyms: careless lazy inattentive negligent

Example: "Her assiduous preparation for the exam paid off when she earned one of the highest scores in the class."

Astute adjective

Short meaning: very sharp, intelligent, and quick to notice or understand things.

Appears frequently in ACT passages describing characters with strong judgment, strategic thinking, or keen observation skills.

Synonyms: shrewd perceptive sharp insightful

Antonyms: unaware slow clueless naive

Example: "The detective’s astute observations allowed her to solve the case long before anyone else noticed the clues."

Asylum noun

Short meaning: protection or safety given to someone fleeing danger; historically, it can also mean a place of shelter or a mental institution.

Often appears in ACT passages involving refugees, political conflict, or characters seeking safety or refuge.

Synonyms: refuge sanctuary safe haven protection

Antonyms: danger exposure vulnerability threat

Example: "Fleeing persecution in her homeland, the journalist requested asylum in a neighboring country."

Auspicious adjective

Short meaning: showing signs of future success; favorable or promising.

Common in ACT reading passages describing new beginnings, important events, or moments that seem likely to lead to good outcomes.

Synonyms: favorable promising fortunate advantageous

Antonyms: unlucky unfortunate inauspicious discouraging

Example: "The clear skies and enthusiastic crowd made it an auspicious day for the school’s grand opening ceremony."

Autonomous adjective

Short meaning: independent; able to make decisions or act without outside control.

Frequently appears in ACT passages about governments, robots, organizations, or individuals gaining independence or self-governance.

Synonyms: independent self-governing self-sufficient free

Antonyms: dependent controlled subordinate subject

Example: "The company encouraged employees to be more autonomous, allowing them to manage projects without constant supervision."

Avarice noun

Short meaning: extreme greed for wealth or material gain.

Appears in ACT passages exploring themes of greed, corruption, moral conflict, or characters motivated by selfish desires.

Synonyms: greed cupidity materialism selfishness

Antonyms: generosity charity selflessness altruism

Example: "The king’s avarice led him to impose heavy taxes, causing great suffering among his people."

Avid adjective

Short meaning: extremely enthusiastic or eager about something.

Common in ACT reading passages describing passionate learners, dedicated hobbyists, or characters with strong interests.

Synonyms: eager enthusiastic passionate keen

Antonyms: uninterested apathetic indifferent unenthusiastic

Example: "As an avid reader, Lena finished an entire novel every weekend."

Belittle verb

Short meaning: to make someone or something seem unimportant or less valuable.

Frequently appears in ACT passages describing dismissive attitudes, criticism, or characters undermining others.

Synonyms: disparage downplay undermine demean

Antonyms: praise compliment encourage uplift

Example: "He felt hurt when his ideas were belittled during the meeting, even though he had worked hard on them."

Belligerent adjective

Short meaning: hostile, aggressive, or ready to fight.

Appears in ACT reading when describing confrontational characters, tense conflicts, or nations at war.

Synonyms: aggressive hostile combative antagonistic

Antonyms: peaceful calm friendly nonviolent

Example: "The coach warned the player to stop acting belligerent toward the referee before he was removed from the game."

Benevolent adjective

Short meaning: kind, generous, and wanting to help others.

Common in ACT passages describing charitable actions, compassionate leaders, or people who use power to help others.

Synonyms: kind generous charitable compassionate

Antonyms: cruel harsh selfish malicious

Example: "The benevolent donor funded scholarships so that students from low-income families could attend college."

Bias noun / verb

Short meaning: as a noun — an unfair preference or prejudice for or against something; as a verb — to influence unfairly.

Very common in ACT reading and science passages when discussing objectivity, media, research methods, or unfair judgment.

Synonyms: prejudice partiality favoritism inclination

Antonyms: fairness objectivity neutrality impartiality

Example: "Researchers must avoid bias when interpreting data to ensure their conclusions are accurate and reliable."

Bolster verb

Short meaning: to support, strengthen, or improve something.

Common in ACT passages where evidence, arguments, confidence, or resources are strengthened or reinforced.

Synonyms: strengthen support reinforce boost

Antonyms: weaken undermine reduce diminish

Example: "The scientist gathered additional data to bolster her argument and convince skeptical reviewers."

Brazen adjective

Short meaning: bold and shameless; showing no embarrassment or fear.

Often appears in ACT passages describing shocking behavior, open defiance, or actions taken without concern for rules or opinions.

Synonyms: shameless bold audacious impudent

Antonyms: modest timid reserved bashful

Example: "In a brazen move, the company ignored repeated warnings and continued to violate safety regulations."

Breach noun / verb

Short meaning: as a noun — a break, violation, or gap; as a verb — to break or fail to follow a rule, law, or agreement.

Common in ACT passages involving laws, contracts, cybersecurity, or situations where trust or rules are violated.

Synonyms: violation break rupture infringement

Antonyms: compliance observance agreement repair

Example: "The data breach exposed thousands of customer records, forcing the company to strengthen its security measures."

Brevity noun

Short meaning: the quality of being brief, short, and concise.

Frequently appears in ACT passages about effective communication, writing style, speeches, or arguments that value clarity over length.

Synonyms: conciseness shortness succinctness compactness

Antonyms: lengthiness wordiness verbosity prolixity

Example: "The editor praised the article for its clarity and brevity, making it easy for readers to understand."

Brusque adjective

Short meaning: abrupt or blunt in manner or speech, often sounding rude.

Often appears in ACT passages describing sharp dialogue, impatient responses, or characters who speak without softness or politeness.

Synonyms: abrupt blunt curt gruff

Antonyms: polite courteous gentle considerate

Example: "The manager’s brusque reply made it clear that he was too busy to answer further questions."

Candid adjective

Short meaning: honest, direct, and truthful, even when the truth may be uncomfortable.

Common in ACT passages describing open conversations, sincere opinions, or moments of honest self-reflection.

Synonyms: honest frank straightforward open

Antonyms: dishonest guarded reserved evasive

Example: "During the interview, the author offered a candid explanation of her early failures and what she learned from them."

Candor noun

Short meaning: the quality of being honest, open, and sincere in expression.

Often appears in ACT passages highlighting honesty in communication, transparent leadership, or sincere dialogue.

Synonyms: honesty frankness openness directness

Antonyms: deception evasion insincerity concealment

Example: "The manager’s candor during the meeting helped build trust and encouraged open discussion among the team."

Capitulate verb

Short meaning: to stop resisting and give in to an opponent or demand.

Common in ACT passages describing negotiations, conflicts, or moments when pressure forces someone to surrender or concede.

Synonyms: surrender yield give in concede

Antonyms: resist persist withstand defy

Example: "After weeks of debate and mounting pressure, the committee finally capitulated to public demands for reform."

Capricious adjective

Short meaning: changing suddenly and unpredictably; impulsive.

Often appears in ACT passages describing unpredictable behavior, sudden mood changes, or forces like weather or leadership decisions.

Synonyms: unpredictable impulsive erratic fickle

Antonyms: consistent stable reliable steady

Example: "The region’s capricious weather made it difficult for farmers to plan their harvests."

Catalyst noun

Short meaning: something that causes or speeds up a significant change or reaction.

Very common in ACT science and social studies passages to describe events, ideas, or people that trigger major changes.

Synonyms: trigger stimulus spark impetus

Antonyms: hindrance obstacle deterrent blockage

Example: "The invention of the internet acted as a catalyst for global communication and rapid technological growth."

Caustic adjective

Short meaning: harsh or sarcastic in a way that can hurt or offend; capable of burning or corroding.

Often appears in ACT passages describing biting criticism, sharp humor, or substances that cause chemical damage.

Synonyms: biting sarcastic scathing corrosive

Antonyms: kind gentle complimentary soothing

Example: "The critic’s caustic remarks about the novel sparked debate but deeply offended the author."

Censure verb / noun

Short meaning: as a verb — to strongly criticize or officially condemn; as a noun — an expression of severe disapproval.

Common in ACT passages involving politics, leadership, ethics, or situations where actions are publicly criticized or condemned.

Synonyms: condemn rebuke reprimand denounce

Antonyms: praise approve commend endorse

Example: "The senator faced censure after the investigation revealed serious ethical violations."

Circumspect adjective

Short meaning: careful to consider all possible consequences before acting or speaking.

Frequently appears in ACT passages describing thoughtful decision-making, cautious behavior, or leaders who act with restraint.

Synonyms: cautious prudent careful wary

Antonyms: reckless careless impulsive rash

Example: "The board took a circumspect approach to the merger, carefully reviewing every potential risk before approving it."

Clairvoyant adjective / noun

Short meaning: able to perceive events beyond normal understanding; unusually insightful or able to predict the future.

Appears in ACT passages discussing intuition, foresight, or metaphorically describing people with exceptional insight.

Synonyms: psychic perceptive insightful visionary

Antonyms: unaware oblivious short-sighted uninformed

Example: "Her seemingly clairvoyant predictions about market trends impressed even the most experienced analysts."

Coerce verb

Short meaning: to force someone to do something using pressure, threats, or intimidation.

Frequently appears in ACT passages involving power dynamics, unethical behavior, or situations where consent is obtained through force.

Synonyms: force compel pressure intimidate

Antonyms: persuade encourage request convince

Example: "The manager tried to coerce employees into working overtime by threatening to cut their hours."

Coherent adjective

Short meaning: logical, clear, and easy to understand; well organized.

Common in ACT passages evaluating arguments, essays, or explanations that flow logically from one idea to the next.

Synonyms: logical clear well-organized consistent

Antonyms: confusing illogical disjointed incoherent

Example: "Her essay presented a coherent argument, guiding the reader smoothly from introduction to conclusion."

Collaborate verb

Short meaning: to work together with others to achieve a shared goal.

Frequently appears in ACT passages about teamwork, scientific research, creative projects, or groups solving problems collectively.

Synonyms: cooperate work together partner team up

Antonyms: compete oppose work alone conflict

Example: "Scientists from different countries collaborated to develop a faster and more effective vaccine."

Compassion noun

Short meaning: deep concern for the suffering of others, along with a desire to help.

Common in ACT passages discussing human values, ethical decisions, caregiving, or characters who respond kindly to hardship.

Synonyms: empathy kindness sympathy benevolence

Antonyms: cruelty indifference harshness coldness

Example: "The nurse showed great compassion by staying late to comfort patients who were feeling anxious."

Comply verb

Short meaning: to act according to a rule, request, or instruction.

Frequently appears in ACT passages involving laws, regulations, authority, or situations requiring obedience or adherence.

Synonyms: obey follow adhere conform

Antonyms: resist defy disobey refuse

Example: "The company was required to comply with environmental regulations to continue operating legally."

Concise adjective

Short meaning: brief but clear; expressing much in few words.

Highly relevant for ACT writing and reading passages where clarity, efficiency, and strong argument structure are emphasized.

Synonyms: brief succinct compact to the point

Antonyms: wordy verbose lengthy rambling

Example: "The teacher encouraged students to write concise responses that clearly addressed the question without unnecessary details."

Condescending adjective

Short meaning: showing a feeling of superiority by talking down to others as if they are less intelligent.

Often appears in ACT literature and social science passages to describe tone, attitude, or dialogue that reflects arrogance or patronizing behavior.

Synonyms: patronizing arrogant snobbish superior

Antonyms: respectful humble courteous considerate

Example: "The speaker’s condescending tone made the audience feel dismissed rather than informed."

Condone verb

Short meaning: to accept or allow something morally wrong or offensive to continue.

Common in ACT passages on ethics, law, and social responsibility—often contrasting what is tolerated versus what is approved.

Synonyms: tolerate permit overlook allow

Antonyms: condemn oppose forbid denounce

Example: "The school made it clear that it would not condone cheating, even if the pressure to succeed was intense."

Conformist noun / adjective

Short meaning: a person who follows accepted rules, traditions, or social norms; showing willingness to fit in.

Often appears in ACT passages discussing social behavior, group pressure, culture, or the contrast between conformity and individuality.

Synonyms: traditionalist follower conventionalist traditional

Antonyms: nonconformist rebel individualist innovator

Example: "In a society that valued strict traditions, anyone who questioned authority was labeled a nonconformist rather than a conformist."

Consensus noun

Short meaning: general agreement among a group of people.

Very common in ACT passages involving group decisions, scientific conclusions, political discussions, or collective opinions.

Synonyms: agreement unity accord common ground

Antonyms: disagreement conflict division dissent

Example: "After hours of discussion, the committee finally reached a consensus on the proposed policy changes."

Conspicuous adjective

Short meaning: easily seen or noticed; attracting attention.

Frequently used in ACT reading passages to describe something that clearly stands out in appearance, behavior, or results.

Synonyms: noticeable obvious prominent striking

Antonyms: hidden inconspicuous subtle unnoticeable

Example: "The scientist’s theory had a conspicuous flaw that reviewers immediately pointed out."

Contend verb

Short meaning: to argue or claim something strongly; to struggle or compete against difficulties.

Common in ACT passages where authors present arguments, defend viewpoints, or describe people facing serious challenges.

Synonyms: argue assert maintain struggle

Antonyms: agree yield concede surrender

Example: "The author contends that access to education is the most powerful tool for reducing inequality."

Conventional adjective

Short meaning: based on what is traditional, usual, or commonly accepted.

Frequently appears in ACT passages contrasting traditional methods or beliefs with innovative or unconventional approaches.

Synonyms: traditional standard customary typical

Antonyms: unconventional innovative radical original

Example: "While the conventional teaching method relied on lectures, the new approach emphasized hands-on learning."

Convergence noun

Short meaning: the process of coming together or moving toward a common point.

Common in ACT science, technology, and social studies passages to describe trends, ideas, or forces gradually uniting.

Synonyms: meeting merging union intersection

Antonyms: divergence separation division dispersion

Example: "The convergence of digital technology and education has transformed how students learn around the world."

Convey verb

Short meaning: to communicate or make an idea, feeling, or message known to others.

Very common in ACT reading and writing passages when authors describe how ideas, emotions, or information are expressed.

Synonyms: communicate express transmit deliver

Antonyms: withhold conceal hide suppress

Example: "Through vivid imagery and precise language, the author conveys a strong sense of urgency to the reader."

Convoluted adjective

Short meaning: extremely complex, complicated, or difficult to follow.

Often appears in ACT passages criticizing unclear arguments, overly complex explanations, or confusing processes.

Synonyms: complicated complex intricate confusing

Antonyms: simple clear straightforward uncomplicated

Example: "The judge criticized the lawyer’s convoluted explanation, noting that a clearer argument would have been more persuasive."

Copious adjective

Short meaning: existing in large quantities; abundant.

Common in ACT science and nonfiction passages to describe large amounts of data, resources, evidence, or rainfall.

Synonyms: abundant plentiful ample profuse

Antonyms: scarce limited meager insufficient

Example: "The researcher gathered copious amounts of evidence to support the new theory."

Corroborate verb

Short meaning: to confirm or support a statement, idea, or finding with additional evidence.

Very common in ACT science, history, and social studies passages where claims are strengthened by data, documents, or independent sources.

Synonyms: confirm support verify substantiate

Antonyms: contradict refute disprove deny

Example: "New satellite data helped corroborate the scientist’s hypothesis about climate patterns."

Credible adjective

Short meaning: believable or trustworthy; able to be accepted as true.

Very common in ACT passages evaluating sources, arguments, scientific claims, or the reliability of evidence.

Synonyms: believable reliable trustworthy convincing

Antonyms: unreliable dubious questionable implausible

Example: "Because the study used a large sample size and clear methodology, its conclusions were considered credible by experts."

Cryptic adjective

Short meaning: mysterious or unclear; difficult to understand.

Often appears in ACT reading passages to describe messages, statements, or texts that are vague and require interpretation.

Synonyms: mysterious enigmatic obscure puzzling

Antonyms: clear explicit straightforward obvious

Example: "The professor’s cryptic explanation left many students unsure of what would be covered on the exam."

Culminate verb

Short meaning: to reach a final, highest, or most important point after a series of events.

Common in ACT passages describing processes, narratives, or developments that build over time and end in a decisive result.

Synonyms: conclude reach result in come to a head

Antonyms: begin start initiate commence

Example: "Years of research and experimentation culminated in a breakthrough that changed modern medicine."

Cursory adjective

Short meaning: done quickly and without careful attention to detail.

Common in ACT passages critiquing shallow analysis, rushed reviews, or actions taken without thorough examination.

Synonyms: brief superficial hasty perfunctory

Antonyms: thorough detailed careful comprehensive

Example: "A cursory glance at the data led to incorrect conclusions that a deeper analysis later disproved."

Daunting adjective

Short meaning: seeming difficult, overwhelming, or intimidating.

Frequently appears in ACT passages describing challenging tasks, complex problems, or situations that initially discourage people.

Synonyms: intimidating overwhelming formidable discouraging

Antonyms: manageable encouraging simple approachable

Example: "Writing a research paper seemed daunting at first, but breaking it into smaller steps made it manageable."

Debilitate verb

Short meaning: to weaken or reduce strength, energy, or effectiveness.

Common in ACT science, health, and social studies passages describing conditions, events, or policies that severely weaken people or systems.

Synonyms: weaken impair sap undermine

Antonyms: strengthen revitalize fortify energize

Example: "The prolonged drought began to debilitate local agriculture, leaving farmers struggling to sustain their crops."

Debunk verb

Short meaning: to expose a false idea, belief, or claim and show that it is not true.

Common in ACT science and nonfiction passages where myths, misconceptions, or unsupported claims are challenged with evidence.

Synonyms: disprove expose refute invalidate

Antonyms: support confirm validate reinforce

Example: "The study helped debunk the long-held belief that the treatment had no real benefits."

Decorum noun

Short meaning: proper and polite behavior according to social rules or expectations.

Common in ACT passages about formal settings, public conduct, ethics, or situations where appropriate behavior is expected.

Synonyms: propriety politeness courtesy respectability

Antonyms: rudeness impropriety disrespect indecorum

Example: "Despite the heated debate, the moderator insisted that all participants maintain decorum throughout the discussion."

Deference noun

Short meaning: respectful submission or yielding to the judgment, opinion, or authority of another.

Frequently appears in ACT passages about social hierarchy, authority, cultural norms, or situations involving respect for expertise or rank.

Synonyms: respect submission regard courtesy

Antonyms: defiance disrespect insubordination resistance

Example: "Out of deference to the senior researcher, the team delayed publishing their findings until further review."

Deleterious adjective

Short meaning: causing harm or damage, often in a gradual or subtle way.

Common in ACT science, health, and policy passages to describe long-term harmful effects on systems, environments, or well-being.

Synonyms: harmful damaging detrimental injurious

Antonyms: beneficial helpful harmless advantageous

Example: "Researchers warned that prolonged exposure to air pollution could have deleterious effects on respiratory health."

Deliberate adjective / verb

Short meaning: as an adjective — done intentionally and with careful thought; as a verb — to think carefully or discuss before making a decision.

Frequently used in ACT passages describing intentional actions, careful planning, or groups thoughtfully weighing options before deciding.

Synonyms: intentional purposeful consider reflect

Antonyms: accidental impulsive hasty reckless

Example: "After hours of deliberate discussion, the committee reached a decision that balanced both risks and benefits."

Delineate verb

Short meaning: to describe, explain, or outline something clearly and precisely.

Common in ACT passages where authors clearly define boundaries, ideas, arguments, or steps in a process.

Synonyms: outline describe define specify

Antonyms: confuse obscure blur misrepresent

Example: "The report carefully delineated the responsibilities of each department to avoid confusion."

Demagogue noun

Short meaning: a leader who seeks power by appealing to people’s emotions, fears, or prejudices rather than reason.

Often appears in ACT history and political passages discussing manipulation of public opinion, rhetoric, and mass influence.

Synonyms: agitator rabble-rouser manipulator populist

Antonyms: statesman leader moderate reformer

Example: "The historian warned that the demagogue gained support by exploiting public fear rather than offering practical solutions."

Denounce verb

Short meaning: to publicly criticize or strongly condemn someone or something.

Frequently used in ACT passages involving politics, ethics, social justice, or public reactions to wrongdoing.

Synonyms: condemn criticize rebuke decry

Antonyms: praise endorse approve support

Example: "Human rights organizations quickly denounced the policy, calling it unfair and discriminatory."

Depict verb

Short meaning: to represent or describe something through words, images, or art.

Very common in ACT reading passages discussing literature, art, history, or how authors and artists present ideas or scenes.

Synonyms: portray illustrate represent describe

Antonyms: misrepresent distort conceal hide

Example: "The novel depicts life in a small village, capturing both its struggles and its quiet beauty."

Derive verb

Short meaning: to obtain something from a source or to develop one thing from another.

Common in ACT science, math, and reading passages when explaining how results, meanings, or benefits come from a specific source.

Synonyms: obtain gain extract originate

Antonyms: lose forfeit discard surrender

Example: "Scientists derive conclusions from careful observation and repeated experimentation."

Derogatory adjective

Short meaning: expressing criticism or disrespect in a way that lowers someone’s reputation.

Often appears in ACT passages analyzing tone, bias, or language that is insulting, dismissive, or unfairly critical.

Synonyms: insulting disparaging demeaning contemptuous

Antonyms: respectful complimentary praising honoring

Example: "The article was criticized for using derogatory language that undermined the credibility of its argument."

Detrimental adjective

Short meaning: causing harm or damage; having a negative effect.

Frequently appears in ACT science, health, and policy passages to describe actions or conditions that negatively impact outcomes.

Synonyms: harmful damaging adverse injurious

Antonyms: beneficial helpful advantageous favorable

Example: "Scientists warned that excessive screen time could be detrimental to children’s cognitive development."

Deviate verb

Short meaning: to move away from an established path, rule, plan, or norm.

Common in ACT passages discussing changes in trends, departures from standards, or unexpected shifts in behavior or results.

Synonyms: diverge depart stray vary

Antonyms: conform adhere follow comply

Example: "When the experiment began to deviate from expected results, the researchers reviewed their methodology."

Digression noun

Short meaning: a temporary departure from the main topic or line of discussion.

Common in ACT reading passages analyzing structure, where authors briefly move away from the main idea before returning.

Synonyms: diversion aside detour tangent

Antonyms: focus continuation relevance concentration

Example: "The author’s brief digression into historical context helped readers better understand the main argument."

Diligent adjective

Short meaning: showing careful and persistent effort; hardworking and attentive.

Frequently appears in ACT passages describing students, researchers, or workers who achieve results through consistent effort.

Synonyms: hardworking industrious conscientious persistent

Antonyms: lazy careless negligent sluggish

Example: "Her diligent preparation allowed her to perform confidently during the final examination."

Discredit verb

Short meaning: to harm someone’s reputation or to make an idea seem untrustworthy or false.

Common in ACT passages analyzing arguments, credibility of sources, or attempts to weaken opposing viewpoints.

Synonyms: undermine refute invalidate disprove

Antonyms: support validate confirm endorse

Example: "The journalist presented verified evidence to discredit the false claims circulating on social media."

Discrepancy noun

Short meaning: a difference or inconsistency between facts, figures, or statements.

Frequently appears in ACT passages that analyze data, reports, or arguments where numbers or claims do not match.

Synonyms: inconsistency difference variation mismatch

Antonyms: agreement consistency uniformity conformity

Example: "Auditors noticed a discrepancy between the reported expenses and the actual financial records."

Disdain noun / verb

Short meaning: a feeling of strong dislike or contempt; to regard something as unworthy.

Common in ACT literature and social science passages to describe attitudes of superiority, rejection, or deep disrespect.

Synonyms: contempt scorn disrespect derision

Antonyms: respect admiration esteem regard

Example: "She spoke with clear disdain for outdated policies that ignored the needs of modern society."

Disparage verb

Short meaning: to speak about someone or something in a way that shows disrespect or belittles their value.

Frequently appears in ACT passages analyzing tone, criticism, bias, or language used to undermine ideas, people, or institutions.

Synonyms: belittle demean criticize denigrate

Antonyms: praise commend respect esteem

Example: "Rather than addressing the issue directly, the speaker chose to disparage his opponent’s qualifications."

Disseminate verb

Short meaning: to spread information, ideas, or knowledge widely.

Very common in ACT science, research, and social studies passages describing how findings, information, or ideas are shared with the public.

Synonyms: spread circulate distribute broadcast

Antonyms: withhold suppress conceal restrict

Example: "The organization used social media to disseminate important health information to communities around the world."

Diverge verb

Short meaning: to move apart from a common point or to differ from an expected course or opinion.

Common in ACT passages describing differing viewpoints, changing trends, or paths that separate from an original direction.

Synonyms: separate branch off vary deviate

Antonyms: converge unite align agree

Example: "As new evidence emerged, experts began to diverge in their interpretations of the study’s results."

Divergent adjective

Short meaning: moving in different directions or having different opinions, ideas, or qualities.

Common in ACT passages describing contrasting viewpoints, varied interpretations of data, or trends that move away from a shared path.

Synonyms: different separate conflicting varying

Antonyms: convergent similar aligned consistent

Example: "The researchers presented divergent explanations for the results, highlighting the complexity of the issue."

Docile adjective

Short meaning: easily taught, managed, or controlled; submissive in behavior.

Often appears in ACT passages describing behavior, temperament, or groups that readily follow direction or authority.

Synonyms: obedient submissive compliant manageable

Antonyms: rebellious defiant unruly resistant

Example: "The trainer preferred docile animals that could be guided easily during the demonstration."

Dogmatic adjective

Short meaning: strongly opinionated and unwilling to accept other views or evidence.

Common in ACT passages analyzing tone, ideology, or arguments where a speaker insists on beliefs without considering alternatives.

Synonyms: rigid opinionated inflexible doctrinaire

Antonyms: open-minded flexible tolerant receptive

Example: "The essay criticizes the dogmatic approach of policymakers who refused to adjust their views despite new evidence."

Eccentric adjective / noun

Short meaning: unusual or unconventional in behavior or thinking; a person who behaves in an odd or distinctive way.

Often appears in ACT literature and social science passages to describe characters, innovators, or individuals who defy social norms.

Synonyms: unconventional quirky odd peculiar

Antonyms: conventional ordinary traditional typical

Example: "The artist was known for his eccentric lifestyle, which often puzzled the public but fueled his creativity."

Eclectic adjective

Short meaning: selecting ideas, styles, or influences from a wide variety of sources.

Common in ACT passages describing art, culture, music, or thinking that blends diverse influences rather than following one tradition.

Synonyms: diverse varied wide-ranging mixed

Antonyms: uniform narrow exclusive specialized

Example: "The museum’s eclectic collection featured artwork ranging from ancient sculptures to modern digital installations."

Egregious adjective

Short meaning: outstandingly bad or shockingly wrong.

Common in ACT passages describing serious mistakes, ethical violations, or actions that stand out because of their severity.

Synonyms: outrageous flagrant shocking blatant

Antonyms: minor trivial acceptable forgivable

Example: "The report highlighted several egregious errors that completely undermined the credibility of the study."

Elaborate adjective / verb

Short meaning: as an adjective — detailed and carefully planned; as a verb — to explain something in more detail.

Frequently appears in ACT reading and writing passages where authors expand ideas, provide detailed explanations, or describe complex designs.

Synonyms: detailed complex expand explain

Antonyms: simple brief summarize condense

Example: "The professor asked the student to elaborate on her answer by providing specific examples from the text."

Elated adjective

Short meaning: extremely happy, joyful, or excited.

Often used in ACT passages to convey strong positive emotions after success, relief, or unexpected good news.

Synonyms: thrilled overjoyed delighted ecstatic

Antonyms: depressed disappointed miserable downcast

Example: "She felt elated after learning that her research proposal had been accepted for publication."

Elicit verb

Short meaning: to draw out or bring forth a response, reaction, or information.

Common in ACT passages involving research, interviews, or analysis where actions or questions produce specific responses.

Synonyms: evoke extract prompt bring out

Antonyms: suppress conceal stifle withhold

Example: "The interviewer asked open-ended questions to elicit honest and detailed responses from the participants."

Elusive adjective

Short meaning: difficult to find, catch, understand, or achieve.

Frequently appears in ACT passages discussing abstract ideas, scientific goals, or truths that remain hard to define or grasp.

Synonyms: hard-to-find evasive slippery intangible

Antonyms: clear obvious attainable reachable

Example: "Despite years of research, a complete cure for the disease remained elusive."

Embellish verb

Short meaning: to add details or decorations to make something more attractive or interesting, sometimes by exaggerating.

Common in ACT passages discussing storytelling, historical accounts, or writing where extra details may enhance—or distort—the truth.

Synonyms: decorate enhance adorn exaggerate

Antonyms: simplify reduce plain understate

Example: "The writer tended to embellish the story with dramatic details that were not supported by historical evidence."

Eminent adjective

Short meaning: well-known, respected, and recognized for expertise or achievements.

Frequently appears in ACT passages about science, history, or culture to describe highly respected scholars, leaders, or experts.

Synonyms: distinguished renowned prominent notable

Antonyms: unknown obscure insignificant ordinary

Example: "The eminent scientist was invited to speak about climate change at the international conference."

Empathy noun

Short meaning: the ability to understand and share the feelings of another person.

Common in ACT passages related to psychology, social behavior, and literature, especially when analyzing human relationships and emotional intelligence.

Synonyms: compassion understanding sensitivity sympathy

Antonyms: indifference apathy coldness insensitivity

Example: "The novel highlights empathy as a crucial trait, allowing characters to connect across cultural and emotional boundaries."

Empirical adjective

Short meaning: based on observation, experience, or experiments rather than theory alone.

Very common in ACT science and research-based passages where conclusions are supported by data, experiments, or real-world evidence.

Synonyms: evidence-based experimental observational factual

Antonyms: theoretical speculative abstract hypothetical

Example: "The scientist relied on empirical evidence from repeated experiments to support her hypothesis."

Emulate verb

Short meaning: to try to match or imitate someone or something, often to achieve similar success.

Common in ACT passages discussing role models, innovation, or progress, where individuals attempt to follow successful examples.

Synonyms: imitate copy mirror replicate

Antonyms: avoid ignore reject diverge

Example: "Young entrepreneurs often emulate industry leaders in hopes of achieving similar levels of success."

Enervating adjective

Short meaning: causing someone to feel drained of energy or strength; exhausting.

Often appears in ACT passages describing harsh conditions, demanding tasks, or environments that weaken physical or mental stamina.

Synonyms: exhausting draining fatiguing debilitating

Antonyms: energizing invigorating refreshing stimulating

Example: "The enervating heat of the desert made it difficult for the researchers to continue their work."

Enhance verb

Short meaning: to improve the quality, value, or effectiveness of something.

Very common in ACT passages related to science, education, technology, and writing, where actions are taken to improve outcomes or performance.

Synonyms: improve increase boost strengthen

Antonyms: diminish reduce weaken impair

Example: "Researchers introduced new techniques to enhance the accuracy of their experimental results."

Entail verb

Short meaning: to involve something as a necessary or unavoidable result.

Common in ACT passages explaining cause-and-effect relationships, responsibilities, or consequences linked to a decision or action.

Synonyms: involve require necessitate imply

Antonyms: exclude avoid eliminate separate

Example: "Accepting the leadership role would entail long hours and significant responsibility."

Ephemeral adjective

Short meaning: lasting for a very short time.

Common in ACT passages describing fleeting moments, temporary trends, or brief natural phenomena.

Synonyms: temporary brief short-lived transient

Antonyms: lasting enduring permanent long-term

Example: "The beauty of the sunrise was ephemeral, fading as the day gradually unfolded."

Equanimity noun

Short meaning: calmness and emotional balance, especially in difficult or stressful situations.

Often appears in ACT passages discussing psychology, leadership, or character traits where emotional control under pressure is emphasized.

Synonyms: composure calmness poise self-control

Antonyms: anxiety agitation panic distress

Example: "Despite the intense questioning, the witness answered with remarkable equanimity."

Erratic adjective

Short meaning: unpredictable or inconsistent in behavior, movement, or pattern.

Common in ACT passages describing irregular behavior, unstable systems, or data patterns that lack consistency.

Synonyms: unpredictable irregular inconsistent volatile

Antonyms: steady consistent predictable stable

Example: "The researcher noted that the device produced erratic results when exposed to extreme temperatures."

Evanescent adjective

Short meaning: quickly fading or disappearing; lasting for a very short time.

Often used in ACT literature and science passages to describe fleeting moments, temporary states, or phenomena that vanish almost as soon as they appear.

Synonyms: fleeting transitory short-lived momentary

Antonyms: enduring lasting permanent persistent

Example: "The evanescent glow of the fireflies disappeared as dawn approached."

Exacerbate verb

Short meaning: to make a problem, situation, or condition worse.

Very common in ACT science, social science, and argumentative passages describing how certain actions or conditions intensify existing problems.

Synonyms: worsen aggravate intensify compound

Antonyms: alleviate ease relieve mitigate

Example: "The lack of proper infrastructure continued to exacerbate the effects of flooding in the coastal region."

Exasperate verb

Short meaning: to irritate, frustrate, or annoy someone intensely.

Common in ACT literature and argumentative passages to describe emotional reactions caused by repeated problems, delays, or unreasonable behavior.

Synonyms: irritate frustrate annoy provoke

Antonyms: soothe calm appease comfort

Example: "The constant interruptions during the presentation began to exasperate both the speaker and the audience."

Exemplary adjective

Short meaning: serving as an excellent model or outstanding example to be followed.

Common in ACT passages praising behavior, performance, or work that sets a standard for others, especially in education, leadership, or ethics.

Synonyms: model outstanding ideal commendable

Antonyms: poor substandard flawed unacceptable

Example: "The teacher highlighted the student’s exemplary research project as a model for the entire class."

Extenuating adjective

Short meaning: making a situation seem less serious or less blameworthy.

Often appears in ACT passages involving law, ethics, or argumentation where circumstances reduce responsibility or severity.

Synonyms: mitigating justifying alleviating excusing

Antonyms: aggravating worsening incriminating damaging

Example: "The judge considered the extenuating circumstances before deciding on a reduced sentence."

Facilitate verb

Short meaning: to make a process or action easier or more efficient.

Very common in ACT passages discussing systems, education, science, or cooperation where methods or tools help improve outcomes.

Synonyms: enable assist simplify promote

Antonyms: hinder obstruct impede complicate

Example: "The new software was designed to facilitate communication between researchers across different institutions."

Feasible adjective

Short meaning: possible to do, achieve, or carry out successfully.

Common in ACT passages evaluating plans, solutions, or proposals to determine whether they are realistic and practical.

Synonyms: possible practical workable viable

Antonyms: impossible impractical unrealistic unworkable

Example: "After reviewing the budget and timeline, the committee concluded that the project was feasible."

Fervent adjective

Short meaning: showing intense passion, enthusiasm, or devotion.

Common in ACT passages describing strong beliefs, emotional commitment, or energetic support for a cause, idea, or goal.

Synonyms: passionate enthusiastic ardent zealous

Antonyms: apathetic indifferent unenthusiastic lukewarm

Example: "The activist delivered a fervent speech that inspired many listeners to take immediate action."

Florid adjective

Short meaning: excessively elaborate or ornate in style; sometimes overly decorative or showy.

Often appears in ACT literature and writing passages to critique writing styles that use too many decorative words instead of clarity.

Synonyms: ornate elaborate flowery overwrought

Antonyms: plain simple concise restrained

Example: "The editor advised the writer to reduce the florid language and focus on clear, direct expression."

Fluctuate verb

Short meaning: to change or vary irregularly, rising and falling over time.

Very common in ACT science, economics, and data-based passages describing changes in prices, temperatures, populations, or measurements.

Synonyms: vary shift oscillate change

Antonyms: stabilize remain constant steady level off

Example: "Daily temperatures fluctuate throughout the week due to shifting weather patterns."

Fortuitous adjective

Short meaning: happening by chance, often resulting in a positive or beneficial outcome.

Common in ACT passages describing unexpected discoveries, coincidences, or events that lead to favorable results.

Synonyms: accidental chance unexpected serendipitous

Antonyms: planned intentional deliberate predictable

Example: "A fortuitous meeting with a former professor led to an unexpected research opportunity."

Frugal adjective

Short meaning: careful with money or resources; avoiding unnecessary expense or waste.

Common in ACT passages on economics, personal finance, or sustainability, highlighting wise use of limited resources.

Synonyms: thrifty economical prudent sparingly

Antonyms: wasteful extravagant lavish spendthrift

Example: "By adopting a frugal lifestyle, the family managed to save enough money for future education expenses."

Gregarious adjective

Short meaning: sociable and enjoying the company of others; fond of being with people.

Common in ACT literature and social science passages describing personality traits, group behavior, or social interaction patterns.

Synonyms: sociable outgoing friendly convivial

Antonyms: reserved introverted solitary aloof

Example: "Her gregarious nature made it easy for her to build friendships in a new environment."

Hackneyed adjective

Short meaning: lacking originality because it has been overused or repeated too often.

Common in ACT reading and writing passages that critique ideas, phrases, or arguments that feel tired, predictable, or unoriginal.

Synonyms: overused trite clichéd stale

Antonyms: original fresh innovative novel

Example: "The reviewer criticized the essay for relying on hackneyed expressions instead of presenting original insights."

Haughty adjective

Short meaning: arrogantly superior and disdainful toward others.

Common in ACT literature and tone-analysis passages to describe characters whose pride or sense of superiority creates conflict.

Synonyms: arrogant condescending snobbish aloof

Antonyms: humble modest respectful courteous

Example: "The haughty tone of the letter suggested that the author believed himself far superior to his critics."

Hedonist noun

Short meaning: a person who believes that pleasure or enjoyment is the most important goal in life.

Often appears in ACT philosophy, ethics, or literature passages when discussing belief systems, values, or lifestyle choices centered on pleasure.

Synonyms: pleasure-seeker sensualist epicurean self-indulgent person

Antonyms: ascetic stoic abstainer austere person

Example: "The philosopher contrasted the hedonist’s pursuit of pleasure with the stoic emphasis on self-control and discipline."

Hypothesis noun

Short meaning: a proposed explanation or assumption made for testing through research or experimentation.

Extremely common in ACT science passages, where students must identify, test, or compare hypotheses based on experimental data.

Synonyms: theory assumption proposition explanation

Antonyms: fact certainty proof conclusion

Example: "The researcher tested her hypothesis by conducting multiple experiments under controlled conditions."

Idiosyncrasy noun

Short meaning: a unique or unusual habit, trait, or characteristic specific to an individual.

Common in ACT literature and social science passages to describe distinctive behaviors, personal quirks, or unconventional traits.

Synonyms: quirk peculiarity oddity individuality

Antonyms: normality conformity uniformity typicality

Example: "One idiosyncrasy of the author was his habit of beginning every chapter with a personal anecdote."

Illicit adjective

Short meaning: illegal or forbidden by law, rules, or accepted standards.

Common in ACT passages discussing law, ethics, history, or social issues where actions violate regulations or moral codes.

Synonyms: illegal unlawful prohibited forbidden

Antonyms: legal lawful permitted authorized

Example: "The investigation uncovered an illicit trade network operating outside international regulations."

Imminent adjective

Short meaning: about to happen very soon, often suggesting urgency or threat.

Very common in ACT science, news-style, and argumentative passages to signal events that are expected to occur shortly.

Synonyms: impending forthcoming approaching looming

Antonyms: distant remote unlikely postponed

Example: "Scientists warned of an imminent volcanic eruption based on rising seismic activity."

Impeccable adjective

Short meaning: flawless; without any mistakes or faults.

Common in ACT passages praising high standards of performance, ethics, or precision in work and behavior.

Synonyms: flawless perfect faultless exemplary

Antonyms: flawed imperfect faulty defective

Example: "The architect’s impeccable attention to detail earned widespread praise for the building’s design."

Impetuous adjective

Short meaning: acting quickly and rashly without careful thought.

Common in ACT literature and psychology passages to describe characters whose sudden decisions lead to conflict or unintended consequences.

Synonyms: rash impulsive hasty reckless

Antonyms: cautious deliberate prudent thoughtful

Example: "His impetuous decision to confront the crowd escalated the situation rather than calming it."

Imply verb

Short meaning: to suggest something without stating it directly.

Extremely common in ACT reading and writing passages, especially in inference questions where meaning is suggested rather than explicitly stated.

Synonyms: suggest hint indicate intimate

Antonyms: state declare express announce

Example: "The author’s tone seems to imply that the policy will have long-term consequences."

Impute verb

Short meaning: to attribute a quality, motive, or responsibility to someone or something.

Common in ACT passages related to argument analysis, law, or ethics, where blame, intent, or responsibility is assigned—sometimes without clear evidence.

Synonyms: attribute ascribe assign credit

Antonyms: deny disclaim reject dissociate

Example: "The journalist refused to impute malicious intent to the scientist without clear supporting evidence."

Incisive adjective

Short meaning: clear, sharp, and direct in analysis, expression, or thinking.

Frequently appears in ACT passages evaluating arguments, critiques, or commentary that cut directly to the core of an issue.

Synonyms: sharp penetrating insightful perceptive

Antonyms: vague blunt superficial unclear

Example: "The critic offered an incisive analysis of the novel, revealing themes that many readers had overlooked."

Inconsequential adjective

Short meaning: not important or significant; having little or no impact.

Common in ACT passages that contrast major causes with minor details, especially in argument evaluation and summary questions.

Synonyms: insignificant trivial minor negligible

Antonyms: important significant meaningful consequential

Example: "Although the error was noticeable, it proved to be inconsequential and did not affect the study’s overall conclusions."

Indifferent adjective

Short meaning: having no particular interest, concern, or sympathy; neither caring nor feeling strongly.

Common in ACT literature, psychology, and social science passages to describe emotional detachment or lack of response to important issues.

Synonyms: apathetic unconcerned disinterested detached

Antonyms: concerned enthusiastic engaged passionate

Example: "Despite the urgency of the issue, many citizens remained indifferent to the proposed policy changes."

Inevitable adjective

Short meaning: certain to happen; unavoidable.

Very common in ACT passages explaining cause-and-effect relationships, where outcomes cannot be prevented despite effort or resistance.

Synonyms: unavoidable inescapable certain bound to happen

Antonyms: avoidable preventable uncertain optional

Example: "Given the rapid spread of the virus, a temporary shutdown of public spaces became inevitable."

Infer verb

Short meaning: to draw a conclusion based on evidence and reasoning rather than direct statements.

Extremely common in ACT reading questions, where students must infer meaning, tone, or intent from clues within the passage.

Synonyms: deduce conclude reason derive

Antonyms: state declare assert specify

Example: "From the author’s cautious language, readers can infer that the proposal remains controversial."

Intrepid adjective

Short meaning: fearless and adventurous, especially in the face of danger or difficulty.

Common in ACT literature, history, and science passages describing explorers, pioneers, or individuals who confront risks with courage.

Synonyms: fearless brave bold undaunted

Antonyms: timid fearful cautious hesitant

Example: "The intrepid explorers ventured into the uncharted wilderness despite the harsh conditions."

Irate adjective

Short meaning: extremely angry or furious.

Common in ACT literature and news-style passages to describe intense emotional reactions caused by injustice, frustration, or provocation.

Synonyms: furious enraged angry livid

Antonyms: calm composed placid serene

Example: "Residents grew irate after learning that essential services would be delayed indefinitely."

Jubilation noun

Short meaning: a feeling of great joy, triumph, or celebration.

Often appears in ACT passages describing public celebrations, victories, or moments of collective happiness following success.

Synonyms: elation rejoicing exultation delight

Antonyms: sorrow despair mourning dejection

Example: "The announcement of the peace agreement was met with widespread jubilation across the nation."

Judicious adjective

Short meaning: showing good judgment, wisdom, and careful thought.

Common in ACT passages discussing decision-making, leadership, policy choices, or balanced evaluations.

Synonyms: wise prudent thoughtful sensible

Antonyms: reckless careless foolish rash

Example: "By making judicious use of limited resources, the organization achieved its goals without unnecessary risk."

Lobbyist noun

Short meaning: a person who tries to influence government decisions or legislation on behalf of a group or cause.

Frequently appears in ACT passages about politics, public policy, lawmaking, and ethical debates.

Synonyms: advocate representative campaigner policy influencer

Antonyms: opponent critic dissenter neutral party

Example: "The lobbyist met with lawmakers to argue for stricter environmental regulations on behalf of conservation groups."

Longevity noun

Short meaning: long duration of life, existence, or usefulness.

Common in ACT passages about health, science, history, technology, and long-term success or impact.

Synonyms: durability endurance long life sustainability

Antonyms: brevity shortness transience mortality

Example: "Scientists study the diet and lifestyle of certain populations to understand the factors behind their longevity."

Lucid adjective

Short meaning: clear, easy to understand, or mentally sound.

Frequently used in ACT passages to describe clear explanations, logical arguments, or moments of mental clarity.

Synonyms: clear coherent intelligible transparent

Antonyms: confusing obscure vague unclear

Example: "The professor offered a lucid explanation of the theory, making even complex ideas easy to grasp."

Malleable adjective

Short meaning: easily shaped, changed, or influenced.

Common in ACT science and social studies passages describing materials, human behavior, or adaptable systems.

Synonyms: flexible adaptable pliable impressionable

Antonyms: rigid inflexible fixed unyielding

Example: "Because the metal was highly malleable, it could be shaped into intricate designs without breaking."

Melancholy noun / adjective

Short meaning: a feeling of deep sadness or a sad, thoughtful mood.

Often appears in ACT literature passages to convey mood, tone, or emotional atmosphere.

Synonyms: sadness sorrow gloom depression

Antonyms: joy happiness cheerfulness optimism

Example: "A sense of melancholy filled the room as the novel’s narrator reflected on lost opportunities."

Mundane adjective

Short meaning: ordinary, dull, or lacking excitement.

Common in ACT passages contrasting routine life with creativity, innovation, or extraordinary events.

Synonyms: ordinary routine commonplace dull

Antonyms: exciting remarkable extraordinary exceptional

Example: "What began as a mundane daily routine eventually inspired the author to explore deeper meaning in ordinary life."

Nebulous adjective

Short meaning: unclear, vague, or not well defined.

Frequently appears in ACT passages describing unclear ideas, uncertain theories, or poorly defined plans.

Synonyms: vague unclear ambiguous hazy

Antonyms: clear definite precise explicit

Example: "The researcher admitted that the explanation was still nebulous and required further evidence."

Nonchalant adjective

Short meaning: calm, relaxed, and showing little concern or worry.

Common in ACT literature and social science passages to describe attitudes, reactions, or emotional tone.

Synonyms: casual unconcerned indifferent cool

Antonyms: anxious concerned worried agitated

Example: "Despite the looming deadline, he remained nonchalant, confident that the work would be finished on time."

Novice noun / adjective

Short meaning: a person who is new to a skill, activity, or field; inexperienced.

Common in ACT passages discussing learning, training, skill development, or early stages of expertise.

Synonyms: beginner learner amateur newcomer

Antonyms: expert veteran professional specialist

Example: "Though a novice in the field of research, she quickly gained confidence through careful observation and practice."

Nuance noun

Short meaning: a subtle difference or fine detail in meaning, expression, or tone.

Frequently tested in ACT reading and writing passages where small distinctions in meaning affect interpretation.

Synonyms: subtlety shade distinction fine point

Antonyms: obviousness bluntness simplicity clarity

Example: "Understanding the nuance in the author’s language helped readers grasp the deeper message of the passage."

Oblivious adjective

Short meaning: unaware of or not noticing what is happening around.

Often appears in ACT passages to describe characters who fail to recognize important details, signals, or consequences.

Synonyms: unaware heedless unmindful ignorant

Antonyms: aware alert conscious attentive

Example: "She walked through the busy station oblivious to the noise and movement surrounding her."

Obsolete adjective

Short meaning: no longer used or useful because it has been replaced by something newer.

Common in ACT passages about technological change, historical shifts, or outdated ideas and practices.

Synonyms: outdated antiquated old-fashioned discarded

Antonyms: modern current innovative relevant

Example: "Advances in digital technology have rendered many traditional recording methods obsolete."

Ominous adjective

Short meaning: suggesting that something bad or unpleasant is likely to happen.

Often used in ACT literature and narrative passages to create tension, foreshadowing, or suspense.

Synonyms: threatening menacing foreboding sinister

Antonyms: promising hopeful reassuring auspicious

Example: "The dark clouds gathering on the horizon gave an ominous warning of the storm to come."

Opulent adjective

Short meaning: very rich, luxurious, or lavish in appearance or style.

Common in ACT literature and history passages describing wealth, social class, or lavish surroundings.

Synonyms: luxurious lavish wealthy sumptuous

Antonyms: poor modest plain austere

Example: "The palace’s opulent décor reflected the immense power and wealth of its rulers."

Orator noun

Short meaning: a skilled public speaker, especially one who delivers formal speeches.

Often appears in ACT history and rhetoric passages discussing speeches, persuasion, and leadership.

Synonyms: speaker public speaker rhetorician speechmaker

Antonyms: listener audience member spectator observer

Example: "The orator captivated the crowd with a powerful speech that called for unity and reform."

Parched adjective

Short meaning: extremely dry or very thirsty.

Common in ACT science and literature passages describing drought, climate conditions, or intense physical states.

Synonyms: dry arid thirsty dehydrated

Antonyms: moist hydrated damp wet

Example: "After weeks without rain, the parched farmland could no longer support healthy crops."

Perfidious adjective

Short meaning: deceitful and untrustworthy, especially by betraying trust.

Often appears in ACT literature and history passages describing betrayal, moral failure, or unethical behavior.

Synonyms: treacherous deceitful traitorous duplicitous

Antonyms: loyal faithful trustworthy honest

Example: "The leader’s perfidious actions shocked his allies, who had trusted him to honor their agreement."

Permeate verb

Short meaning: to spread through or be present throughout something.

Common in ACT science and social studies passages describing diffusion, influence, or widespread impact.

Synonyms: spread penetrate pervade infuse

Antonyms: block contain restrict confine

Example: "The scent of fresh bread seemed to permeate the entire building, drawing people toward the bakery."

Plausible adjective

Short meaning: seeming reasonable or believable; likely to be true.

Frequently appears in ACT science and argument passages when evaluating explanations, hypotheses, or claims.

Synonyms: believable reasonable credible convincing

Antonyms: unlikely implausible far-fetched doubtful

Example: "Based on the available evidence, the scientist proposed a plausible explanation for the sudden change in temperature."

Portray verb

Short meaning: to describe, represent, or show someone or something in a particular way.

Common in ACT literature, media, and social studies passages analyzing how characters, events, or ideas are represented.

Synonyms: depict represent illustrate describe

Antonyms: misrepresent distort conceal hide

Example: "The novel portrays the city as both vibrant and unforgiving, shaping the reader’s understanding of its characters."

Precocious adjective

Short meaning: developing abilities or maturity earlier than usual for one’s age.

Common in ACT passages describing unusually advanced children, early talent, or accelerated intellectual growth.

Synonyms: advanced gifted exceptional early-developing

Antonyms: immature underdeveloped slow delayed

Example: "The precocious student mastered complex mathematical concepts years before most of her peers."

Predominantly adverb

Short meaning: mainly, mostly, or for the most part.

Frequently used in ACT science, social studies, and data-based passages to describe majority trends or dominant characteristics.

Synonyms: mostly largely primarily chiefly

Antonyms: rarely occasionally minorly incidentally

Example: "The region is predominantly agricultural, with most residents relying on farming for their livelihood."

Pretentious adjective

Short meaning: trying to appear more important, intelligent, or impressive than one really is.

Often used in ACT literature and critique passages to express negative judgment about style, behavior, or attitude.

Synonyms: showy affected pompous ostentatious

Antonyms: modest humble unassuming simple

Example: "Critics dismissed the film as pretentious, arguing that its complex symbolism lacked genuine depth."

Procrastinate verb

Short meaning: to delay or put off doing something, often unnecessarily.

Common in ACT passages discussing productivity, decision-making, time management, or human behavior.

Synonyms: delay postpone put off stall

Antonyms: act complete address advance

Example: "Students who procrastinate often find themselves under unnecessary stress as deadlines approach."

Prosperity noun

Short meaning: a state of success, wealth, or well-being.

Common in ACT history, economics, and social studies passages discussing growth, stability, or societal success.

Synonyms: success wealth thriving abundance

Antonyms: poverty decline hardship recession

Example: "Periods of technological innovation often lead to widespread prosperity and improved living standards."

Provocative adjective

Short meaning: causing a strong reaction, especially by being challenging or controversial.

Frequently appears in ACT passages analyzing ideas, art, or statements that challenge opinions or stimulate debate.

Synonyms: stimulating controversial challenging inciting

Antonyms: soothing calming neutral inoffensive

Example: "The author’s provocative arguments encouraged readers to question long-held beliefs."

Prudent adjective

Short meaning: showing careful judgment and good sense, especially to avoid risk.

Common in ACT passages about decision-making, policy choices, finance, and responsible behavior.

Synonyms: wise cautious sensible judicious

Antonyms: reckless careless imprudent rash

Example: "Given the uncertain economy, it was prudent to save resources rather than expand too quickly."

Querulous adjective

Short meaning: complaining in a persistent, whining, or petulant manner.

Often appears in ACT literature and social commentary passages to describe tone, attitude, or character behavior.

Synonyms: complaining whiny petulant grumbling

Antonyms: content patient cheerful agreeable

Example: "The critic’s querulous tone distracted from the substance of his argument and weakened its impact."

Rancorous adjective

Short meaning: showing deep bitterness, resentment, or long-lasting hostility.

Often used in ACT literature, history, and social conflict passages to describe enduring anger or unresolved disputes.

Synonyms: bitter resentful hostile acrimonious

Antonyms: friendly amicable cordial harmonious

Example: "Years after the disagreement, their relationship remained rancorous, shaped by unresolved resentment."

Reclusive adjective

Short meaning: avoiding the company of others; living a solitary or withdrawn life.

Common in ACT literature and biographical passages describing personality traits or isolated lifestyles.

Synonyms: withdrawn isolated solitary introverted

Antonyms: sociable outgoing gregarious friendly

Example: "The reclusive author rarely appeared in public, choosing instead to focus on writing in solitude."

Reconciliation noun

Short meaning: the act of restoring friendly relations after a disagreement or conflict.

Common in ACT history, social studies, and literature passages discussing conflict resolution, peace efforts, or repaired relationships.

Synonyms: settlement resolution peace harmony

Antonyms: conflict discord estrangement hostility

Example: "Through honest dialogue and compromise, the two communities achieved reconciliation after years of tension."

Refute verb

Short meaning: to prove that a statement or argument is wrong.

Frequently appears in ACT science and argument passages where claims are challenged using evidence or logic.

Synonyms: disprove counter debunk contradict

Antonyms: support confirm uphold validate

Example: "The researcher presented new data to refute the long-standing theory."

Reinforce verb

Short meaning: to strengthen or support something, making it more effective or secure.

Common in ACT passages involving arguments, structures, learning, or scientific processes where strength or support is emphasized.

Synonyms: strengthen support bolster fortify

Antonyms: weaken undermine erode diminish

Example: "Additional evidence was used to reinforce the author’s central argument."

Renovation noun

Short meaning: the act of repairing, improving, or updating something to make it better or more modern.

Common in ACT passages about urban development, architecture, history, or restoration of older structures.

Synonyms: restoration remodeling renewal upgrading

Antonyms: decay neglect deterioration ruin

Example: "The renovation of the historic building preserved its original character while adding modern safety features."

Resilient adjective

Short meaning: able to recover quickly from difficulties or adapt well to change.

Common in ACT passages describing individuals, communities, or systems that withstand challenges or setbacks.

Synonyms: strong adaptable flexible tough

Antonyms: fragile vulnerable weak brittle

Example: "Despite repeated natural disasters, the coastal community proved resilient and rebuilt each time."

Restrained adjective

Short meaning: controlled, limited, or not showing strong emotion or behavior.

Common in ACT literature and analytical passages describing controlled emotions, measured behavior, or limited expression.

Synonyms: controlled reserved moderate subdued

Antonyms: uncontrolled expressive excessive uninhibited

Example: "Although the results were disappointing, she responded with a restrained calm that surprised her colleagues."

Reverence noun

Short meaning: deep respect, admiration, or awe for someone or something.

Often appears in ACT literature, history, and cultural passages to describe respect for tradition, authority, or ideals.

Synonyms: respect admiration awe veneration

Antonyms: disrespect contempt disdain irreverence

Example: "The community spoke with reverence about the leader whose actions had shaped generations."

Sagacity noun

Short meaning: the quality of being wise, insightful, and able to make sound judgments.

Common in ACT passages discussing leadership, philosophy, ethics, or thoughtful decision-making.

Synonyms: wisdom insight prudence discernment

Antonyms: foolishness naivety imprudence recklessness

Example: "Her sagacity allowed her to anticipate potential problems and choose the most effective solution."

Scarce adjective

Short meaning: limited in quantity; hard to find or obtain.

Common in ACT science, economics, and social studies passages discussing limited resources or supply constraints.

Synonyms: rare limited insufficient meager

Antonyms: abundant plentiful ample copious

Example: "In arid regions, clean drinking water is scarce and must be carefully managed."

Scrutinize verb

Short meaning: to examine something very carefully and closely.

Frequently used in ACT science, research, and argument passages where evidence, data, or claims are closely examined.

Synonyms: examine inspect analyze study

Antonyms: ignore overlook neglect glance at

Example: "Researchers scrutinized the data carefully before drawing any conclusions about the experiment."

Spontaneous adjective

Short meaning: happening naturally and suddenly, without planning or preparation.

Common in ACT passages describing natural reactions, human behavior, biological processes, or unplanned events.

Synonyms: impulsive unplanned instinctive automatic

Antonyms: planned deliberate intentional calculated

Example: "The audience erupted in spontaneous applause after the unexpected announcement."

Spurious adjective

Short meaning: false, misleading, or not genuine; lacking a real basis.

Frequently used in ACT science and argument passages to describe false claims, unreliable data, or flawed reasoning.

Synonyms: false bogus misleading unfounded

Antonyms: genuine valid authentic legitimate

Example: "Researchers dismissed the spurious correlation after discovering errors in the data collection process."

Stringent adjective

Short meaning: very strict, precise, or demanding; enforced firmly.

Common in ACT passages discussing laws, regulations, policies, or scientific standards that must be strictly followed.

Synonyms: strict rigorous severe exacting

Antonyms: lenient flexible relaxed permissive

Example: "The laboratory followed stringent safety protocols to ensure accurate and reliable experimental results."

Submissive adjective

Short meaning: willing to obey or accept the authority or control of others.

Often appears in ACT passages about social behavior, power dynamics, psychology, or historical relationships.

Synonyms: obedient compliant docile yielding

Antonyms: assertive dominant rebellious defiant

Example: "The study examined how submissive behavior can influence group decision-making under pressure."

Subsequent adjective

Short meaning: coming after something else in time; following.

Common in ACT passages describing sequences of events, cause-and-effect relationships, and historical timelines.

Synonyms: following later ensuing succeeding

Antonyms: previous prior earlier preceding

Example: "The initial experiment failed, but subsequent trials produced more reliable results."

Substantiate verb

Short meaning: to prove that something is true by providing evidence or support.

Frequently used in ACT passages when authors present data, research findings, or evidence to support a claim.

Synonyms: support confirm validate verify

Antonyms: disprove refute contradict deny

Example: "The scientist used additional data to substantiate her theory about climate change."

Subtle adjective

Short meaning: delicate, not obvious, or difficult to notice at first glance.

Common in ACT passages describing nuanced ideas, hidden meanings, or slight changes in tone or behavior.

Synonyms: delicate slight faint nuanced

Antonyms: obvious blatant clear overt

Example: "The author made a subtle shift in tone, signaling a change in attitude toward the subject."

Succinct adjective

Short meaning: expressed clearly and briefly, without unnecessary words.

Frequently used in ACT passages to praise writing, explanations, or arguments that are clear yet compact.

Synonyms: concise brief compact to-the-point

Antonyms: verbose wordy lengthy rambling

Example: "The professor gave a succinct explanation that clarified the complex theory in just a few sentences."

Superficial adjective

Short meaning: existing or occurring on the surface only; lacking depth or seriousness.

Common in ACT passages criticizing shallow analysis, appearances, or incomplete understanding.

Synonyms: shallow surface-level cosmetic external

Antonyms: deep thorough profound substantive

Example: "A superficial reading of the article misses the author’s deeper argument about social change."

Superfluous adjective

Short meaning: more than is needed; unnecessary or excessive.

Common in ACT passages criticizing extra details, redundant words, or unnecessary additions.

Synonyms: unnecessary excessive redundant extra

Antonyms: essential necessary vital indispensable

Example: "The editor removed several superfluous sentences to make the argument clearer and more direct."

Surreptitious adjective

Short meaning: done secretly or stealthily to avoid attention or detection.

Often appears in ACT passages describing hidden actions, secret plans, or behavior meant to go unnoticed.

Synonyms: secretive covert stealthy clandestine

Antonyms: open overt transparent public

Example: "The journalist uncovered surreptitious meetings between officials that were never disclosed to the public."

Tactful adjective

Short meaning: careful and sensitive in dealing with others so as not to offend or upset them.

Often used in ACT passages highlighting diplomacy, social awareness, or skillful communication in sensitive situations.

Synonyms: diplomatic considerate discreet thoughtful

Antonyms: tactless blunt insensitive rude

Example: "The manager gave tactful feedback that addressed the problem without embarrassing the employee."

Tenacious adjective

Short meaning: holding firmly to a goal, belief, or task; not giving up easily.

Frequently appears in ACT passages describing persistence, determination, or sustained effort despite obstacles.

Synonyms: persistent determined resolute steadfast

Antonyms: weak yielding quitful indecisive

Example: "Her tenacious pursuit of evidence eventually led to a breakthrough in the investigation."

Tentative adjective

Short meaning: not certain or fixed; done with hesitation or caution.

Common in ACT passages describing early plans, cautious conclusions, or ideas that may change with more evidence.

Synonyms: uncertain hesitant provisional experimental

Antonyms: definite certain confident decisive

Example: "The researchers offered a tentative explanation, noting that further testing was required."

Transient adjective

Short meaning: lasting only for a short time; temporary.

Frequently used in ACT passages to describe short-lived conditions, temporary states, or brief experiences.

Synonyms: temporary brief short-lived fleeting

Antonyms: permanent lasting enduring stable

Example: "The city’s population surge was transient, fading once the construction project ended."

Undermine verb

Short meaning: to weaken or damage something gradually, often in a subtle or indirect way.

Common in ACT passages describing how arguments, trust, authority, or systems are weakened over time rather than destroyed outright.

Synonyms: weaken erode sabotage subvert

Antonyms: strengthen support reinforce bolster

Example: "Frequent contradictions in the report began to undermine the credibility of the research."

Venerable adjective

Short meaning: deserving great respect because of age, wisdom, or long-standing importance.

Often used in ACT passages to describe respected institutions, traditions, leaders, or figures honored for their long influence.

Synonyms: respected esteemed revered honored

Antonyms: disrespected contemptible dishonored insignificant

Example: "The venerable university is admired not only for its age but also for its lasting contributions to research and education."

Viable adjective

Short meaning: capable of working successfully; practical and effective.

Frequently used in ACT passages evaluating whether plans, solutions, or methods are realistic and workable.

Synonyms: feasible workable practical effective

Antonyms: impractical unworkable impossible ineffective

Example: "After reviewing the data, the committee agreed that the proposal was viable and worth pursuing."

Vindicate verb

Short meaning: to clear someone of blame or suspicion; to prove something is right or justified.

Common in ACT passages discussing evidence, justice, or arguments that ultimately prove a claim or person correct.

Synonyms: exonerate justify defend clear

Antonyms: condemn blame accuse incriminate

Example: "New DNA evidence helped vindicate the defendant, overturning a conviction that had stood for years."

Wary adjective

Short meaning: cautious and alert, especially because of possible danger or risk.

Frequently appears in ACT passages describing careful judgment, skepticism, or alertness toward potential problems.

Synonyms: cautious alert watchful guarded

Antonyms: careless trusting reckless naive

Example: "Scientists remain wary of drawing conclusions until the experiment is repeated and verified."

Zealous adjective

Short meaning: showing great enthusiasm, passion, or dedication for a cause or goal.

Common in ACT passages describing intense commitment, strong advocacy, or energetic pursuit of beliefs or ideals.

Synonyms: enthusiastic passionate ardent fervent

Antonyms: apathetic indifferent unenthusiastic lukewarm

Example: "The zealous volunteers worked tirelessly to promote environmental awareness in their community."