crucial

adjective

cru·​cial ˈkrü-shəl 

1

a

: important, significant

… what use we make of them will be the crucial question.

—Stanley Kubrick

Vitamins are crucial for maintaining good health.

b

: important or essential as resolving a crisis : decisive

She played a crucial role in the negotiations.

c

: marked by final determination of a doubtful issue

the crucial game of a series

2

archaic : cruciform

Synonyms

• critical
• key
• pivotal
• vital

Choose the Right Synonym for crucial

acute, critical, crucial mean of uncertain outcome.

acute stresses intensification of conditions leading to a culmination or breaking point.

an acute housing shortage

critical adds to acute implications of imminent change, of attendant suspense, and of decisiveness in the outcome.

the war has entered a critical phase

crucial suggests a dividing of the ways and often a test or trial involving the determination of a future course or direction.

a crucial vote

Examples of crucial in a Sentence

Vitamins are crucial for maintaining good health.

It's crucial that we arrive before 8 o'clock.

Teachers are crucial to the success of the school.

She played a crucial role in the meeting.

Recent Examples on the Web

Gold, which is universally recognized and not tied to credit or another counterparty, is a crucial reserve. —Sarah Min, CNBC, 27 Feb. 2025

For animals like dogs, cats, and monkeys, ear movement helps track sounds, which is crucial for detecting predators or prey. —Clarissa Brincat, Popular Science, 27 Feb. 2025

Having the capability of catching the Starship booster is crucial for SpaceX, giving the company a completely reusable vehicle that is able to fly again. —Eric Lagatta, USA TODAY, 27 Feb. 2025

Because carbon monoxide is undetectable without specialized detectors, prevention measures such as proper ventilation, regular maintenance of fuel-burning appliances, and the use of carbon monoxide alarms are crucial for safety. —David Faris, Newsweek, 27 Feb. 2025

Word History

Etymology

French, from Latin cruc-, crux cross

First Known Use

1706, in the meaning defined at sense 2

Rhymes for crucial

• trucial

Kids Definition

crucial

adjective

cru·​cial ˈkrü-shəl 

1

: being a final or very important test or decision : decisive

the crucial game of a series

2

: very important : significant

water is a crucial element in our weather

crucially

ˈkrüsh-(ə-)lē

adverb

Etymology

from French crucial "having the form of a cross, being or involving a crisis," from Latin cruc-, crux "cross, trouble, torture" — related to cross, crucify, crux