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 of crucial

• key
• critical
• 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

Cook County Public Guardian Charles Golbert, whose staff oversees the cases of more than 600 adults under guardianship and has helped champion the bill, said face-to-face meetings are standard practice in his office prior to appointment and are crucial to properly assessing the person’s needs. —Christy Gutowski, Chicago Tribune, 3 May 2026

This observational power is crucial for gathering the data needed to calibrate eruptive mass loss. —Paul Sutter, Space.com, 3 May 2026

Where to Drink As many soccer fans will tell you, cold beer is a crucial part of the beautiful game—especially within the fiery embrace of Dallas summer. —Jonathan Thompson, Travel + Leisure, 3 May 2026

The proposal comes at a crucial time in Missouri politics, setting up several chaotic and dueling scenarios. —Kacen Bayless, Kansas City Star, 3 May 2026

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