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Catrina Coffey

Top 20 ACT Vocabulary Words

Hi there, Magooshers!

As I mentioned in the Top Tips post, the ACT will more commonly test secondary definitions of common words than esoteric or abstruse vocabulary. With that in mind, here are the top 20 ACT vocabulary words you should know — along with their definitions and parts of speech.

Bear in mind that the second and third definitions of the words on this list are important, too!

Top 20 ACT Words

Word Part of Speech Definition(s)
1 adhere verb to stick to a surface or substance [or] to follow a practice or belief
2 anticipate verb to regard as probable [or] to expect or predict
3 characteristic adjective a special quality of a person, thing, or group
4 compose verb to write or create [or] to constitute or make up (water is composed of hydrogen and oxygen)
5 critical adjective expressing criticism or disapproval [or] relating to the careful judgments of critics (usually about books, art, movies, etc.) [or] using careful judgment about the good and bad parts of something
6 determine verb to make an official decision, based on evidence or facts [or] to be the cause or reason for something [or] to learn something by getting information
7 differentiate verb to recognize what makes someone or something different [or] to make someone or something appear different [or] to become different in the process of development
8 engage verb to occupy or attract someone’s interest or attention [or] to participate in something
9 glaring adjective giving or reflecting a strong light [or] very obvious or conspicuous
10 hypothesis noun a supposition or proposed explanation based on limited evidence, used as a starting point for further investigation
11 imminent adjective about to happen
12 inevitable adjective unavoidable [or] when used as a noun, a situation that is unavoidable (I don’t want to be here when the inevitable occurs)
13 intuition noun the ability to understand something before using conscious reasoning [or] something that one knows before thinking about it; a “gut feeling.”
14 justify verb to show or prove to be right [or] to be a good reason for doing something
15 omit verb to intentionally leave something or someone out [or] to leave something undone
16 precede verb to come before in time, order, or position [or] to go in front or ahead of
17 redundant adjective no longer useful, superfluous, extra [or] able to be left out without sacrificing meaning or usefulness
18 relevant adjective appropriate to the matter at hand
19 trivial adjective of small value or importance [or] a person only concerned with unimportant things
20 uniform adjective not changing in form or character, or similar in form in character to other things [or] a piece of clothing that is part of a uniform


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About Catrina Coffey

Catrina graduated from Rider University with a B.A. in English. She’s been helping students prepare for standardized tests since 2011. In her spare time, you can find her reading anything within arms’ reach, playing video games, correcting grammar, or studying word derivations. (Did you know that procrastinate comes from the Latin word cras, which means “tomorrow”?)

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