crucial

American  

[kroo-shuhl] / ˈkru ʃəl /

adjective

1. involving an extremely important decision or result; decisive; critical.

   a crucial experiment.

   Synonyms:

   significant, essential, vital, momentous

2. severe; trying.

3. of the form of a cross; cross-shaped.

---

crucial British  

/ ˈkruːʃəl /

adjective

1. involving a final or supremely important decision or event; decisive; critical

2. informal very important

3. 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

• cruciality noun
• crucially adverb
• noncrucial adjective
• noncrucially adverb
• precrucial adjective

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.

Example Sentences

Investor bullish sentiment rose to 46% this week, but coming earnings and Federal Reserve meeting will be crucial for market direction.

From Barron's • Apr. 23, 2026

With each goal potentially proving crucial in a tense title race, City may view a victory with a solitary Erling Haaland goal as a missed opportunity to boost their goal difference.

From BBC • Apr. 22, 2026

For those listed on public exchanges, share buybacks will be a crucial metric for gauging management’s conviction in their own valuations.

From The Wall Street Journal • Apr. 22, 2026

While that doesn’t currently mean the oil is getting through the Strait of Hormuz, it could put the nation’s oil first in line to reach supply-starved buyers when the crucial waterway reopens.

From MarketWatch • Apr. 22, 2026

The discovery of America was crucial in legitimizing innovation because within forty years no one disputed that it really was an unprecedented event, and one that could not be ignored.

From "The Invention of Science" by David Wootton

Related Words

• central
• compelling
• deciding
• decisive
• essential
• imperative
• momentous
• necessary
• pivotal
• pressing
• touchy
• urgent
• vital