SAT & ACT

150 Most Difficult ACT Vocabulary Words You Must Know in 2025

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Ruchi Khanted
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Is the ACT vocabulary section giving you nightmares? Do you find yourself staring blankly at passages filled with words that seem straight out of a dictionary?

This is where your vocabulary revolution begins. We’ve compiled a list of 150+ essential ACT vocabulary words, each carefully chosen to prepare you to understand hidden meanings and challenging sentence structures. This isn’t just another list of dry definitions. We’ll provide engaging examples and strategic tips to help you not just memorize, but truly understand and apply these words.

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How Does the ACT Test Vocabulary?

The ACT is moving away from isolated vocabulary memorization and toward assessing your ability to understand words in context. While direct definition questions still exist, they’re less frequent. This shift prioritizes your ability to comprehend complex passages and grasp nuanced meanings based on the surrounding text.

Even with the reduced focus on definitions, a robust vocabulary remains crucial for good ACT scores. Why?

  • Emphasis on context: The ACT vocabulary questions now test your ability to define and grasp the meaning of unfamiliar words within a specific passage.
  • Focus on common words: While some questions might feature uncommon words, most test vocabulary you’ve likely encountered before. For example, words like “cumbersome,” “thorny,” “strenuous,” and “gawky” might not instantly recall every nuance, but you’ve likely seen them before, and the context helps you choose the correct answer.

Read Also: ACT Test Dates for 2024 in USA

150+ ACT Vocabulary Words You Must Know

This comprehensive table compiles 150+ Most Difficult ACT vocabulary words you must know in 2024. It equips you to take the Reading and Writing sections with confidence. Each word comes with a clear definition and an informative example sentence for deeper understanding.

Word Meaning Example Sentence
Abate To lessen in intensity or degree The storm abated, and the sun came out.
Abjure To formally renounce or reject something The king abjured his claim to the throne.
Abridge To shorten The publisher had to abridge the novel for the children’s edition.
Acquiesce To accept reluctantly but without protest She had no choice but to acquiesce to their demands.
Acumen Sharply insightful; keen judgment The detective’s sharp acumen helped crack the case.
Aesthetic Concerned with beauty or the appreciation of beauty The minimalist design had a pleasing aesthetic.
Alleviate To relieve Taking aspirin can alleviate a headache.
Altruistic Unselfishly concerned for others Her altruistic actions earned her the community’s admiration.
Amalgamate To merge or combine into one; unite The company will amalgamate its two marketing departments for better efficiency.
Amicable Friendly; peaceable The neighbors reached an amicable agreement regarding the property line.
Apathy Lack of interest or emotion The student’s apathy towards learning was evident in his grades.
Appal Shock or horrify The brutality of the war appalled the entire world.
Appease To calm or pacify someone by giving them what they want The king tried to appease the angry mob with promises of reform.
Apprehensive Feeling anxious or fearful; worried John was apprehensive about his upcoming presentation.
Arcane Mysterious and difficult to understand; obscure The ancient text contained arcane symbols and rituals.
Belie To contradict or misrepresent His calm demeanor belied the turmoil inside him.
Bellicose Demonstrating aggression or willingness to fight His bellicose demeanor often led to arguments with his peers.
Belligerent Hostile and aggressive The belligerent customer argued with the store manager.
Benevolent Kind-hearted The benevolent woman spent her weekends volunteering at the shelter.
Bolster To support or strengthen The new evidence helped bolster their case in court.
Bombastic Pompous; inflated language The politician’s bombastic speeches failed to impress the voters.
Cacophony Harsh, discordant mixture of sounds The city streets were filled with the cacophony of traffic.
Cadence The rhythm or flow of sound The poet used cadence to create a musical effect in his verses.
Candor Frankness; openness in speech He appreciated her candor during their conversation.
Capitulate To surrender The army had no choice but to capitulate to the enemy forces.
Capricious Unpredictable; impulsive Her capricious nature made it difficult to anticipate her actions.
Caustic Severely critical or sarcastic; harsh The comedian’s caustic remarks left the audience squirming.
Chicanery Deceitful trickery or cheating The politician’s chicanery was exposed by the media.
Circumspect Cautious; wary He was circumspect in his dealings with strangers.
Cogent Convincing; reasonable She presented a cogent argument in favor of her proposal.
Concomitant Accompanying or associated with something else; existing at the same time The rise in popularity of social media had a concomitant increase in cyberbullying.
Conspicuous Easy to see or notice; prominent Her bright red dress made her conspicuous in the crowd.
Conundrum A difficult problem or question The conundrum of balancing work and family life is a common challenge.
Debilitate To weaken The illness debilitated him, and he was unable to work.
Deleterious Harmful; damaging Smoking has deleterious effects on one’s health.
Delineate To describe or portray precisely The artist delineated the features of the landscape.
Desiccate Dry out completely The hot desert sun desiccated the plants.
Diatribe A forceful and bitter verbal attack The politician’s speech turned into a diatribe against his opponents.
Dilemma A situation where a difficult choice must be made between two equally undesirable options He faced a dilemma: accept the promotion and move away or stay in his current city and miss out on the opportunity.
Disdain Contempt; scorn She looked at him with disdain after his rude comment.
Disingenuous Insincere or misleading; lacking in candor Her disingenuous apology only made things worse.
Disparate Fundamentally different; unrelated The two sisters had disparate interests and hobbies.
Dogmatic Asserting opinions as if they were facts His dogmatic attitude made it difficult to have a constructive discussion.
Ebullient Overflowing with excitement; exhilarated She was ebullient upon hearing the news of her promotion.
Effervescent Lively and bubbly; full of enthusiasm The crowd was effervescent with excitement at the concert.
Effusive Warmly enthusiastic and expressive She gave her best friend an effusive hug.
Egregious Outstandingly bad; shocking The team’s performance was egregious, resulting in a humiliating defeat.
Elicit To draw out or evoke a response The teacher used open-ended questions to elicit thoughtful answers from her students.
Eloquent Fluent or persuasive in speaking or writing The speaker delivered an eloquent speech that moved the audience to tears.
Enervate To weaken or sap the energy of something; make powerless The long commute enervated her, leaving her too tired to cook dinner.
Enigmatic Mysterious; puzzling The enigmatic smile on her face left everyone curious.
Ephemeral Lasting for a very short time The beauty of the cherry blossoms is ephemeral.
Exacerbate To make something worse; intensify The argument only exacerbated the already tense situation.
Facetious Treating serious issues with inappropriate humor His facetious remarks during the meeting were not appreciated.
Fastidious Very attentive to detail; meticulous She was fastidious about keeping her house clean.
Fervent Intensely passionate or earnest He was a fervent supporter of human rights.
Fortuitous Happening by chance or luck It was fortuitous that she found the lost keys.
Frugal Thrifty She lived a frugal lifestyle, saving money wherever she could.
Furtive Secretive; sly The thief cast a furtive glance around before stealing the jewels.
Garrulous Excessively talkative The garrulous old man told stories for hours.
Glib Fluent but insincere or shallow His glib response to the question revealed his lack of understanding.
Gregarious Sociable Mark was gregarious and made friends easily at the party.
Hackneyed Overused; lacking significance The actor’s speech was filled with hackneyed phrases.
Hapless Unfortunate; unlucky The hapless traveler lost his wallet on the trip.
Haughty Arrogant The haughty aristocrat looked down on those she considered beneath her.
Histrionic Overly dramatic; theatrical Her histrionic reaction to the news startled everyone.
Hubris Excessive pride or self-confidence His hubris led to his downfall in the end.
Imbibe To drink or absorb He imbibed too much wine at the party and ended up having a headache the next day.
Impasse A situation in which progress is impossible; a deadlock The negotiations reached an impasse.
Impassive Showing no emotion or feeling; indifferent The actor remained impassive despite the chaos unfolding around him.
Impetuous Acting without thinking His impetuous decision led to regret later on.
Imprudent Lacking good judgment; unwise It was imprudent of her to go swimming alone in the dark.
Incandescent Emitting light as a result of being heated The incandescent bulb illuminated the room.
Incessant Continuing without interruption The incessant noise from the construction site was annoying.
Ineffable Too great or extreme to be expressed in words The beauty of the sunset was ineffable.
Ingenious Clever, original, and inventive The engineer’s design for the bridge was ingenious and solved a major obstacle.
Inimical Hostile or harmful The harsh environment was inimical to the survival of the plants.
Innuendo An indirect or suggestive remark His innuendo implied that she was responsible for the mistake.
Insidious Proceeding in a gradual, subtle way The insidious disease went undetected until it was too late.
Interminable Seemingly endless; very long and tiring The meeting seemed interminable, dragging on for hours.
Intransigent Unwilling to compromise or change one’s mind; stubborn The intransigent leader refused to listen to any alternative solutions.
Jocular Playful and humorous; lighthearted He told a jocular joke to break the tension in the room.
Jubilant Extremely joyful The team was jubilant after winning the championship.
Juxtapose To place side by side for comparison The artist juxtaposed light and dark in her paintings.
Kindle To ignite The teacher hoped to kindle an interest in science among her students.
Knell The sound of a bell, especially when rung solemnly for a death or funeral The knell of the church bell signaled the end of the service.
Lachrymose Tending to weep or cry often; tearful The lachrymose movie made the entire audience cry.
Laconic Using few words; concise The detective gave a laconic response to the question.
Lament To mourn; express sorrow or regret The villagers lamented the loss of their crops to the drought.
Languid Lacking energy; slow and relaxed The hot weather made him feel languid and sleepy.
Languish To become weak or feeble The plants began to languish during the drought.
Lethargic Sluggish After a heavy meal, he felt lethargic and sleepy.
Maladroit Clumsy or awkward in movement or behavior He tried to help, but his maladroit attempts only made things worse.
Malaise A general feeling of discomfort, illness, or uneasiness A sense of malaise hung over the city after the natural disaster.
Malicious Intending to do harm The rumors were spread with malicious intent.
Mawkish Excessively sentimental; sappy The movie’s mawkish ending left the audience rolling their eyes.
Meticulous Paying great attention to detail; careful and precise The scientist was meticulous in her lab work, ensuring accurate results.
Mollify To soothe; appease She tried to mollify her angry boss with an apology.
Meticulous Extremely careful about details The artist was meticulous in every brushstroke.
Nebulous Unclear; vague The instructions were nebulous, leaving us confused.
Nefarious Wicked or criminal The gang was involved in nefarious activities throughout the city.
Nonchalant Appearing casually unconcerned or indifferent He acted nonchalant about the news, but deep down, he was worried.
Nonplussed Surprised and confused She was nonplussed by the sudden turn of events.
Oblivious Unaware She was so deep in thought that she was oblivious to her surroundings.
Obfuscate To make something unclear or difficult to understand The politician’s answer obfuscated the real issue rather than addressing it directly.
Obsequious Obedient or attentive to an excessive or servile degree The obsequious assistant always agreed with his boss.
Opaque Not transparent; not allowing light to pass through The windows were opaque, preventing anyone from seeing inside.
Ostensible Apparent or seeming, but not necessarily true His ostensible reason for being late was car trouble, but it was probably something else.
Ostentatious Showy; intended to impress others Her ostentatious display of wealth made others uncomfortable.
Paradigm A typical example or pattern The discovery was a paradigm shift in the field of medicine.
Parsimonious Stingy; excessively frugal His parsimonious nature made him reluctant to spend money.
Pedantic Overly concerned with minor details and rules; fussy The professor’s pedantic lectures often bored his students.
Pernicious Harmful The pernicious effects of smoking are well-documented.
Plausible Believable; credible His explanation seemed plausible, given the circumstances.
Portentous Suggesting the occurrence of something important or ominous The dark clouds were a portentous sign of an approaching storm.
Precipitous Sudden and steep; abrupt The stock market took a precipitous drop after the bad news.
Precipitate Sudden and steep; abrupt The stock market took a precipitous drop after the bad news.
Quell To suppress; put an end to The police were called to quell the riot.
Querulous Complaining His querulous nature made him difficult to work with.
Quixotic Idealistic but impractical His quixotic dreams of world peace were admirable but unrealistic.
Rebuke To criticize or express disapproval of someone or something The teacher gently rebuked the student for talking in class.
Recondite Difficult to understand; obscure The book was filled with recondite philosophical concepts.
Reprehensible Deserving criticism or condemnation His actions were deemed reprehensible by society.
Resilient Able to recover quickly from difficulties Despite facing many setbacks, she remained resilient and optimistic.
Reticent Reserved; reluctant to speak She was reticent about discussing her personal life.
Sagacious Wise The sagacious old man gave valuable advice to the young prince.
Salient Most noticeable or important The salient features of the proposal were highlighted.
Sanguine Optimistic; cheerful Despite the setback, he remained sanguine about the future.
Sedulous Showing great care and persistent effort He was a sedulous student who always went above and beyond.
Solicitous Showing care and concern for the welfare of others; attentive The nurse was solicitous of the patient’s needs.
Soliloquy A speech delivered by a character alone on stage The actor delivered a powerful soliloquy that revealed his character’s inner turmoil.
Stoic Not showing feeling or emotion; unemotional He remained stoic even when faced with great adversity.
Sumptuous Rich, splendid, and luxurious The king lived a sumptuous life in his palace.
Supercilious Behaving as if one thinks one is superior to others; arrogant The professor’s supercilious attitude alienated his students.
Superfluous Unnecessary; more than enough The extra decorations were superfluous and cluttered the room.
Surreptitious Secretive; stealthy She made a surreptitious exit from the party.
Taciturn Reserved; uncommunicative The taciturn man preferred listening to speaking.
Tenacious Persistent She was tenacious in her pursuit of a career in medicine.
Tenuous Weak or unreliable; flimsy The evidence supporting their claim was very tenuous.
Transient Lasting for only a short time The transient feeling of happiness soon faded away.
Trepidation Fear; apprehension She approached the haunted house with trepidation.
Ubiquitous Being everywhere at the same time In today’s world, smartphones are ubiquitous.
Unanimous In complete agreement The committee reached a unanimous decision.
Vacillate To waver between different opinions or actions He vacillated between accepting the job offer and staying at his current position.
Vehement Showing strong feeling; passionate He was vehement in his opposition to the proposal.
Venerable Worthy of respect due to age, wisdom, or character The venerable professor had taught at the university for over 50 years.
Wane To decrease gradually in size or intensity The moon’s brightness began to wane as it entered its last phase.
Wary Cautious She was wary of strangers offering her help.
Wistful Yearning; longing with sadness As she looked at the old photographs, she felt wistful.
Xenophile A person who is attracted to foreign cultures or people As a xenophile, she loved traveling and experiencing new cultures.
Xenophobia Fear or hatred of foreigners or strangers The rise of xenophobia in the country was concerning.
Yearn To have a strong desire or longing He yearned for adventure and travel.
Zeal Enthusiasm She tackled her new project with great zeal.
Zealous Filled with zeal; fervent The volunteers were zealous in their efforts to help.
Zephyr A gentle breeze The zephyr rustled the leaves of the trees in the park.

Note: This list serves as a valuable tool, not a mandatory checklist. Focus on learning the words that resonate most with you and gradually expanding your vocabulary.

Our methodology

To curate this list, we meticulously analyzed every publicly available official ACT practice exam. We scanned not just the questions but also the answer choices and passages in both the Reading and Writing sections. Additionally, we have leveraged our expertise in standardized testing to select words with high a statistical appearance probability.

Why it matters

While memorizing every word might seem difficult, becoming familiar with most of them offers significant benefits. You’ll be able to:

  • Grasp the nuanced vocabulary choices used in the passages, which will enable you to accurately understand their overall tone and message.
  • Recognizing key vocabulary terms will significantly speed up your ability to interpret information and answer questions correctly.

Read Also: 20 Critical ACT Math Formulas for 2024

How Should You Study ACT Vocabulary Words?

Scoring well in the ACT’s Reading and English sections isn’t just about memorizing a dictionary’s worth of words. It’s about understanding context and how meaning shifts within a sentence.

  • Flashcards are your friends, but not the old-fashioned kind. Utilize apps like Anki that employ spaced repetition, a scientifically proven method that shows you flashcards strategically based on your recall difficulty. Focus on words you struggle with, not just reviewing everything equally.
  • Don’t treat vocabulary in isolation. Immerse yourself in rich reading materials like news articles, classic literature, or even well-written blogs. Pay attention to how unfamiliar words are used, inferring their meaning from the surrounding context. This not only builds vocabulary but also hones your reading comprehension skills.
  • Get into the word’s origins! Understanding root words and prefixes can simplify the meaning of many related words. For example, “ambivalent” comes from “ambi” (both) and “valere” (to be worth), making its meaning of having mixed feelings instantly clear.
  • Memory tricks can be powerful tools. Create silly stories, funny images, or even rhymes to associate with challenging words. The more bizarre and memorable it is, the better it sticks!
  • Don’t just study; actively test yourself. Utilize official ACT practice tests or online resources with vocabulary-focused quizzes. Analyze your mistakes, understand why certain answer choices were wrong, and learn from them.
  • Turn vocabulary practice into a fun challenge. Play online vocabulary games, compete with friends using spaced repetition apps, or reward yourself for achieving milestones. Making it enjoyable boosts motivation and retention.
  • The ACT loves testing your understanding of similar and opposite meanings. Pay attention to the synonyms and antonyms provided when learning new words. This refines your understanding of the semantic nuances that the test often hinges on.

Read Also: 5 Best ACT Tips and Tricks to Achieve Your Desired Score

From the Desk of Yocket

While cramming vocabulary lists can feel like a necessity for the ACT, we believe that it’s important to approach it from a slightly different perspective. Instead of viewing it as a rote memorization exercise, consider vocabulary building a valuable investment in your overall language skills. Expanding your vocabulary goes far beyond the ACT. It helps you to express yourself more effectively, understand complex ideas, and have nuanced conversations. This skill set benefits you in academics, your career, and even personal interactions.

The ACT doesn’t simply test your ability to use synonyms. It assesses your understanding of words within context. By actively engaging with challenging material and analyzing how unfamiliar words are used, you develop critical thinking skills that transcend the test. Instead of mindlessly memorizing definitions, focus on understanding the nuances of a word’s meaning, its synonyms and antonyms, and how it interacts with other words in a sentence. Yocket experts will assist you, leading to better retention and making you a more confident reader and writer.

150+ ACT Vocabulary Words You Must Know

This comprehensive table compiles 150+ Most Difficult ACT vocabulary words you must know in 2024. It equips you to take the Reading and Writing sections with confidence. Each word comes with a clear definition and an informative example sentence for deeper understanding.

Word Meaning Example Sentence
Abate To lessen in intensity or degree The storm abated, and the sun came out.
Abjure To formally renounce or reject something The king abjured his claim to the throne.
Abridge To shorten The publisher had to abridge the novel for the children’s edition.
Acquiesce To accept reluctantly but without protest She had no choice but to acquiesce to their demands.
Acumen Sharply insightful; keen judgment The detective’s sharp acumen helped crack the case.
Aesthetic Concerned with beauty or the appreciation of beauty The minimalist design had a pleasing aesthetic.
Alleviate To relieve Taking aspirin can alleviate a headache.
Altruistic Unselfishly concerned for others Her altruistic actions earned her the community’s admiration.
Amalgamate To merge or combine into one; unite The company will amalgamate its two marketing departments for better efficiency.
Amicable Friendly; peaceable The neighbors reached an amicable agreement regarding the property line.
Apathy Lack of interest or emotion The student’s apathy towards learning was evident in his grades.
Appal Shock or horrify The brutality of the war appalled the entire world.
Appease To calm or pacify someone by giving them what they want The king tried to appease the angry mob with promises of reform.
Apprehensive Feeling anxious or fearful; worried John was apprehensive about his upcoming presentation.
Arcane Mysterious and difficult to understand; obscure The ancient text contained arcane symbols and rituals.
Belie To contradict or misrepresent His calm demeanor belied the turmoil inside him.
Bellicose Demonstrating aggression or willingness to fight His bellicose demeanor often led to arguments with his peers.
Belligerent Hostile and aggressive The belligerent customer argued with the store manager.
Benevolent Kind-hearted The benevolent woman spent her weekends volunteering at the shelter.
Bolster To support or strengthen The new evidence helped bolster their case in court.
Bombastic Pompous; inflated language The politician’s bombastic speeches failed to impress the voters.
Cacophony Harsh, discordant mixture of sounds The city streets were filled with the cacophony of traffic.
Cadence The rhythm or flow of sound The poet used cadence to create a musical effect in his verses.
Candor Frankness; openness in speech He appreciated her candor during their conversation.
Capitulate To surrender The army had no choice but to capitulate to the enemy forces.
Capricious Unpredictable; impulsive Her capricious nature made it difficult to anticipate her actions.
Caustic Severely critical or sarcastic; harsh The comedian’s caustic remarks left the audience squirming.
Chicanery Deceitful trickery or cheating The politician’s chicanery was exposed by the media.
Circumspect Cautious; wary He was circumspect in his dealings with strangers.
Cogent Convincing; reasonable She presented a cogent argument in favor of her proposal.
Concomitant Accompanying or associated with something else; existing at the same time The rise in popularity of social media had a concomitant increase in cyberbullying.
Conspicuous Easy to see or notice; prominent Her bright red dress made her conspicuous in the crowd.
Conundrum A difficult problem or question The conundrum of balancing work and family life is a common challenge.
Debilitate To weaken The illness debilitated him, and he was unable to work.
Deleterious Harmful; damaging Smoking has deleterious effects on one’s health.
Delineate To describe or portray precisely The artist delineated the features of the landscape.
Desiccate Dry out completely The hot desert sun desiccated the plants.
Diatribe A forceful and bitter verbal attack The politician’s speech turned into a diatribe against his opponents.
Dilemma A situation where a difficult choice must be made between two equally undesirable options He faced a dilemma: accept the promotion and move away or stay in his current city and miss out on the opportunity.
Disdain Contempt; scorn She looked at him with disdain after his rude comment.
Disingenuous Insincere or misleading; lacking in candor Her disingenuous apology only made things worse.
Disparate Fundamentally different; unrelated The two sisters had disparate interests and hobbies.
Dogmatic Asserting opinions as if they were facts His dogmatic attitude made it difficult to have a constructive discussion.
Ebullient Overflowing with excitement; exhilarated She was ebullient upon hearing the news of her promotion.
Effervescent Lively and bubbly; full of enthusiasm The crowd was effervescent with excitement at the concert.
Effusive Warmly enthusiastic and expressive She gave her best friend an effusive hug.
Egregious Outstandingly bad; shocking The team’s performance was egregious, resulting in a humiliating defeat.
Elicit To draw out or evoke a response The teacher used open-ended questions to elicit thoughtful answers from her students.
Eloquent Fluent or persuasive in speaking or writing The speaker delivered an eloquent speech that moved the audience to tears.
Enervate To weaken or sap the energy of something; make powerless The long commute enervated her, leaving her too tired to cook dinner.
Enigmatic Mysterious; puzzling The enigmatic smile on her face left everyone curious.
Ephemeral Lasting for a very short time The beauty of the cherry blossoms is ephemeral.
Exacerbate To make something worse; intensify The argument only exacerbated the already tense situation.
Facetious Treating serious issues with inappropriate humor His facetious remarks during the meeting were not appreciated.
Fastidious Very attentive to detail; meticulous She was fastidious about keeping her house clean.
Fervent Intensely passionate or earnest He was a fervent supporter of human rights.
Fortuitous Happening by chance or luck It was fortuitous that she found the lost keys.
Frugal Thrifty She lived a frugal lifestyle, saving money wherever she could.
Furtive Secretive; sly The thief cast a furtive glance around before stealing the jewels.
Garrulous Excessively talkative The garrulous old man told stories for hours.
Glib Fluent but insincere or shallow His glib response to the question revealed his lack of understanding.
Gregarious Sociable Mark was gregarious and made friends easily at the party.
Hackneyed Overused; lacking significance The actor’s speech was filled with hackneyed phrases.
Hapless Unfortunate; unlucky The hapless traveler lost his wallet on the trip.
Haughty Arrogant The haughty aristocrat looked down on those she considered beneath her.
Histrionic Overly dramatic; theatrical Her histrionic reaction to the news startled everyone.
Hubris Excessive pride or self-confidence His hubris led to his downfall in the end.
Imbibe To drink or absorb He imbibed too much wine at the party and ended up having a headache the next day.
Impasse A situation in which progress is impossible; a deadlock The negotiations reached an impasse.
Impassive Showing no emotion or feeling; indifferent The actor remained impassive despite the chaos unfolding around him.
Impetuous Acting without thinking His impetuous decision led to regret later on.
Imprudent Lacking good judgment; unwise It was imprudent of her to go swimming alone in the dark.
Incandescent Emitting light as a result of being heated The incandescent bulb illuminated the room.
Incessant Continuing without interruption The incessant noise from the construction site was annoying.
Ineffable Too great or extreme to be expressed in words The beauty of the sunset was ineffable.
Ingenious Clever, original, and inventive The engineer’s design for the bridge was ingenious and solved a major obstacle.
Inimical Hostile or harmful The harsh environment was inimical to the survival of the plants.
Innuendo An indirect or suggestive remark His innuendo implied that she was responsible for the mistake.
Insidious Proceeding in a gradual, subtle way The insidious disease went undetected until it was too late.
Interminable Seemingly endless; very long and tiring The meeting seemed interminable, dragging on for hours.
Intransigent Unwilling to compromise or change one’s mind; stubborn The intransigent leader refused to listen to any alternative solutions.
Jocular Playful and humorous; lighthearted He told a jocular joke to break the tension in the room.
Jubilant Extremely joyful The team was jubilant after winning the championship.
Juxtapose To place side by side for comparison The artist juxtaposed light and dark in her paintings.
Kindle To ignite The teacher hoped to kindle an interest in science among her students.
Knell The sound of a bell, especially when rung solemnly for a death or funeral The knell of the church bell signaled the end of the service.
Lachrymose Tending to weep or cry often; tearful The lachrymose movie made the entire audience cry.
Laconic Using few words; concise The detective gave a laconic response to the question.
Lament To mourn; express sorrow or regret The villagers lamented the loss of their crops to the drought.
Languid Lacking energy; slow and relaxed The hot weather made him feel languid and sleepy.
Languish To become weak or feeble The plants began to languish during the drought.
Lethargic Sluggish After a heavy meal, he felt lethargic and sleepy.
Maladroit Clumsy or awkward in movement or behavior He tried to help, but his maladroit attempts only made things worse.
Malaise A general feeling of discomfort, illness, or uneasiness A sense of malaise hung over the city after the natural disaster.
Malicious Intending to do harm The rumors were spread with malicious intent.
Mawkish Excessively sentimental; sappy The movie’s mawkish ending left the audience rolling their eyes.
Meticulous Paying great attention to detail; careful and precise The scientist was meticulous in her lab work, ensuring accurate results.
Mollify To soothe; appease She tried to mollify her angry boss with an apology.
Meticulous Extremely careful about details The artist was meticulous in every brushstroke.
Nebulous Unclear; vague The instructions were nebulous, leaving us confused.
Nefarious Wicked or criminal The gang was involved in nefarious activities throughout the city.
Nonchalant Appearing casually unconcerned or indifferent He acted nonchalant about the news, but deep down, he was worried.
Nonplussed Surprised and confused She was nonplussed by the sudden turn of events.
Oblivious Unaware She was so deep in thought that she was oblivious to her surroundings.
Obfuscate To make something unclear or difficult to understand The politician’s answer obfuscated the real issue rather than addressing it directly.
Obsequious Obedient or attentive to an excessive or servile degree The obsequious assistant always agreed with his boss.
Opaque Not transparent; not allowing light to pass through The windows were opaque, preventing anyone from seeing inside.
Ostensible Apparent or seeming, but not necessarily true His ostensible reason for being late was car trouble, but it was probably something else.
Ostentatious Showy; intended to impress others Her ostentatious display of wealth made others uncomfortable.
Paradigm A typical example or pattern The discovery was a paradigm shift in the field of medicine.
Parsimonious Stingy; excessively frugal His parsimonious nature made him reluctant to spend money.
Pedantic Overly concerned with minor details and rules; fussy The professor’s pedantic lectures often bored his students.
Pernicious Harmful The pernicious effects of smoking are well-documented.
Plausible Believable; credible His explanation seemed plausible, given the circumstances.
Portentous Suggesting the occurrence of something important or ominous The dark clouds were a portentous sign of an approaching storm.
Precipitous Sudden and steep; abrupt The stock market took a precipitous drop after the bad news.
Precipitate Sudden and steep; abrupt The stock market took a precipitous drop after the bad news.
Quell To suppress; put an end to The police were called to quell the riot.
Querulous Complaining His querulous nature made him difficult to work with.
Quixotic Idealistic but impractical His quixotic dreams of world peace were admirable but unrealistic.
Rebuke To criticize or express disapproval of someone or something The teacher gently rebuked the student for talking in class.
Recondite Difficult to understand; obscure The book was filled with recondite philosophical concepts.
Reprehensible Deserving criticism or condemnation His actions were deemed reprehensible by society.
Resilient Able to recover quickly from difficulties Despite facing many setbacks, she remained resilient and optimistic.
Reticent Reserved; reluctant to speak She was reticent about discussing her personal life.
Sagacious Wise The sagacious old man gave valuable advice to the young prince.
Salient Most noticeable or important The salient features of the proposal were highlighted.
Sanguine Optimistic; cheerful Despite the setback, he remained sanguine about the future.
Sedulous Showing great care and persistent effort He was a sedulous student who always went above and beyond.
Solicitous Showing care and concern for the welfare of others; attentive The nurse was solicitous of the patient’s needs.
Soliloquy A speech delivered by a character alone on stage The actor delivered a powerful soliloquy that revealed his character’s inner turmoil.
Stoic Not showing feeling or emotion; unemotional He remained stoic even when faced with great adversity.
Sumptuous Rich, splendid, and luxurious The king lived a sumptuous life in his palace.
Supercilious Behaving as if one thinks one is superior to others; arrogant The professor’s supercilious attitude alienated his students.
Superfluous Unnecessary; more than enough The extra decorations were superfluous and cluttered the room.
Surreptitious Secretive; stealthy She made a surreptitious exit from the party.
Taciturn Reserved; uncommunicative The taciturn man preferred listening to speaking.
Tenacious Persistent She was tenacious in her pursuit of a career in medicine.
Tenuous Weak or unreliable; flimsy The evidence supporting their claim was very tenuous.
Transient Lasting for only a short time The transient feeling of happiness soon faded away.
Trepidation Fear; apprehension She approached the haunted house with trepidation.
Ubiquitous Being everywhere at the same time In today’s world, smartphones are ubiquitous.
Unanimous In complete agreement The committee reached a unanimous decision.
Vacillate To waver between different opinions or actions He vacillated between accepting the job offer and staying at his current position.
Vehement Showing strong feeling; passionate He was vehement in his opposition to the proposal.
Venerable Worthy of respect due to age, wisdom, or character The venerable professor had taught at the university for over 50 years.
Wane To decrease gradually in size or intensity The moon’s brightness began to wane as it entered its last phase.
Wary Cautious She was wary of strangers offering her help.
Wistful Yearning; longing with sadness As she looked at the old photographs, she felt wistful.
Xenophile A person who is attracted to foreign cultures or people As a xenophile, she loved traveling and experiencing new cultures.
Xenophobia Fear or hatred of foreigners or strangers The rise of xenophobia in the country was concerning.
Yearn To have a strong desire or longing He yearned for adventure and travel.
Zeal Enthusiasm She tackled her new project with great zeal.
Zealous Filled with zeal; fervent The volunteers were zealous in their efforts to help.
Zephyr A gentle breeze The zephyr rustled the leaves of the trees in the park.

Note: This list serves as a valuable tool, not a mandatory checklist. Focus on learning the words that resonate most with you and gradually expanding your vocabulary.

Our methodology

To curate this list, we meticulously analyzed every publicly available official ACT practice exam. We scanned not just the questions but also the answer choices and passages in both the Reading and Writing sections. Additionally, we have leveraged our expertise in standardized testing to select words with high a statistical appearance probability.

Why it matters

While memorizing every word might seem difficult, becoming familiar with most of them offers significant benefits. You’ll be able to:

  • Grasp the nuanced vocabulary choices used in the passages, which will enable you to accurately understand their overall tone and message.
  • Recognizing key vocabulary terms will significantly speed up your ability to interpret information and answer questions correctly.

Read Also: 20 Critical ACT Math Formulas for 2024

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How Should You Study ACT Vocabulary Words?

Scoring well in the ACT’s Reading and English sections isn’t just about memorizing a dictionary’s worth of words. It’s about understanding context and how meaning shifts within a sentence.

  • Flashcards are your friends, but not the old-fashioned kind. Utilize apps like Anki that employ spaced repetition, a scientifically proven method that shows you flashcards strategically based on your recall difficulty. Focus on words you struggle with, not just reviewing everything equally.
  • Don’t treat vocabulary in isolation. Immerse yourself in rich reading materials like news articles, classic literature, or even well-written blogs. Pay attention to how unfamiliar words are used, inferring their meaning from the surrounding context. This not only builds vocabulary but also hones your reading comprehension skills.
  • Get into the word’s origins! Understanding root words and prefixes can simplify the meaning of many related words. For example, “ambivalent” comes from “ambi” (both) and “valere” (to be worth), making its meaning of having mixed feelings instantly clear.
  • Memory tricks can be powerful tools. Create silly stories, funny images, or even rhymes to associate with challenging words. The more bizarre and memorable it is, the better it sticks!
  • Don’t just study; actively test yourself. Utilize official ACT practice tests or online resources with vocabulary-focused quizzes. Analyze your mistakes, understand why certain answer choices were wrong, and learn from them.
  • Turn vocabulary practice into a fun challenge. Play online vocabulary games, compete with friends using spaced repetition apps, or reward yourself for achieving milestones. Making it enjoyable boosts motivation and retention.
  • The ACT loves testing your understanding of similar and opposite meanings. Pay attention to the synonyms and antonyms provided when learning new words. This refines your understanding of the semantic nuances that the test often hinges on.

Read Also: 5 Best ACT Tips and Tricks to Achieve Your Desired Score

From the Desk of Yocket

While cramming vocabulary lists can feel like a necessity for the ACT, we believe that it’s important to approach it from a slightly different perspective. Instead of viewing it as a rote memorization exercise, consider vocabulary building a valuable investment in your overall language skills. Expanding your vocabulary goes far beyond the ACT. It helps you to express yourself more effectively, understand complex ideas, and have nuanced conversations. This skill set benefits you in academics, your career, and even personal interactions.

The ACT doesn’t simply test your ability to use synonyms. It assesses your understanding of words within context. By actively engaging with challenging material and analyzing how unfamiliar words are used, you develop critical thinking skills that transcend the test. Instead of mindlessly memorizing definitions, focus on understanding the nuances of a word’s meaning, its synonyms and antonyms, and how it interacts with other words in a sentence. Yocket experts will assist you, leading to better retention and making you a more confident reader and writer.

Frequently Asked Questions about ACT Vocabulary

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How many vocabulary words do I need to learn for the ACT?

Does the ACT have synonyms or antonyms?

What are some common mistakes to avoid when learning vocab for the ACT?

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