crucial
Americanadjective
-
involving an extremely important decision or result; decisive; critical.
a crucial experiment.
- Synonyms:
- significant, essential, vital, momentous
-
severe; trying.
-
of the form of a cross; cross-shaped.
adjective
-
involving a final or supremely important decision or event; decisive; critical
-
informal very important
-
slang very good
Usage
What does crucial mean? Crucial means extremely important or involving an extremely important decision or course of action. Close synonyms are critical and decisive. The word crucial is usually used to describe pivotal moments, choices, or actions that will affect everything that follows, as in We’re at a crucial point in the process—we need to make some big decisions. Sometimes, crucial is simply used to describe something that’s extremely important, as in Getting enough sleep is crucial for staying healthy. Example: I can’t express how absolutely crucial it is to surround yourself with the right friends.
Other Word Forms
Etymology
Origin of crucial
First recorded in 1700–10; from Latin cruci- (stem of crux cross ( def. ) ) + -al 1 ( def. )
Explanation
The word crucial describes something that is important or essential to success, like the crucial dress rehearsals that ensure everything will run smoothly on your play's opening night. Usage experts insist that the word crucial should be used only to describe something that is truly critical for solving a problem or for resolving a situation, such as a crucial vote that determines a final outcome. In this case the crucial vote is decisive: it determines the outcome. But the word has gained popularity as a way to say that something is important. You might hear someone say, for example, that it is crucial to allow employees to vote on the new schedule to make them feel like they’re part of the process. In this case the sense is “important”: nothing decisive is taking place.
Vocabulary lists containing crucial
List 1
Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!
Jim Burke's Academic Vocabulary List
Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!
Walk Two Moons
Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
A sense of assurance is crucial to her, in part because she has experienced homelessness and housing insecurity.
From MarketWatch ● Sep. 16, 2026
This rate is crucial because it influences borrowing costs of mortgages, credit cards, auto loans and other lending that undergirds the economy.
From MarketWatch ● Sep. 15, 2026
It's crucial for Canada to be "connected to partners on which we can rely," Carney said.
From Barron's ● Sep. 15, 2026
Meanwhile, Bitcoin declined 2.1% to $77,384, ahead of a crucial procedural vote in the Senate on proposed legislation that could offer regulatory clarity across digital assets.
From The Wall Street Journal ● Sep. 15, 2026
Looking back in 1662, Boyle hailed the experiment at the Puy-de-Dôme as the experimentum crucis, the crucial experiment, which had validated a new physics.
From "The Invention of Science" by David Wootton
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
