cru·​cial | \ ˈkrü-shəl How to pronounce crucial (audio) \

Definition of crucial

1 archaic : cruciform
2a : important or essential as resolving a crisis : decisive She played a crucial role in the negotiations.
b : marked by final determination of a doubtful issue the crucial game of a series
c : important, significant … what use we make of them will be the crucial question.— Stanley Kubrick Vitamins are crucial for maintaining good health.

Keep scrolling for more

Synonyms for crucial


critical, key, pivotal, vital

Visit the Thesaurus for More 

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.
See More

Recent Examples on the Web

Every blade of grass, every ray of sun and every rain drop is crucial to our survival. Caroline Hallemann, Town & Country, "Prince Harry Just Gave a Powerful Speech at This Year's WE Day," 6 Mar. 2019 The sporting body says the bylaw is crucial to protecting the interests... Sara Germano, WSJ, "Olympic Athletes in Germany Seize Advertising Win," 27 Feb. 2019 Epstein’s connections are crucial to understanding his story. Jane Coaston, Vox, "Jeffrey Epstein, the convicted sex offender who is friends with Donald Trump and Bill Clinton, explained," 22 Feb. 2019 Survivor Phil Saviano, who was crucial to the Boston Globe’s 2002 expose that first revealed the extent of the abuse and cover-up by clergy, was more optimistic. Nicole Winfield, The Seattle Times, "Pope strives to fight cleric sex abuse with Vatican summit," 20 Feb. 2019 Because cervical cancer generally progresses slowly, early diagnosis is often crucial to detecting the disease when there are curative treatment options available. Leana Wen, SELF, "Before I Was President of Planned Parenthood, I Was Diagnosed With Cervical Cancer at a Routine Screening," 28 Jan. 2019 These registration numbers are a window into the crucial issue of enthusiasm. Jeet Heer, The New Republic, "Democrats enjoy a huge party registration advantage in midterms.," 10 July 2018 But the notion was quickly dropped, even as President Trump pushed a hard line on immigration, a crucial issue for his political base. CBS News, "Trump's "zero tolerance" policy sowed confusion from start," 1 July 2018 If Kavanaugh proves the crucial fifth vote to overturn Roe, there are multiple ways in which the Supreme Court could do so. Matt Ford, The New Republic, "How the Supreme Court Kills Roe v. Wade," 11 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'crucial.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

See More

First Known Use of crucial

1706, in the meaning defined at sense 1

History and Etymology for crucial

French, from Latin cruc-, crux cross

Keep scrolling for more

Learn More about crucial

Dictionary Entries near crucial







crucian carp

Statistics for crucial

Last Updated

13 Mar 2019

Look-up Popularity

Time Traveler for crucial

The first known use of crucial was in 1706

See more words from the same year

Keep scrolling for more

More Definitions for crucial



English Language Learners Definition of crucial

: extremely important


cru·​cial | \ ˈkrü-shəl How to pronounce crucial (audio) \

Kids Definition of crucial

1 : being a final or very important test or decision : decisive a crucial battle
2 : very important : significant Water is a crucial element in our weather.

Keep scrolling for more

More from Merriam-Webster on crucial

Thesaurus: All synonyms and antonyms for crucial

Spanish Central: Translation of crucial

Nglish: Translation of crucial for Spanish Speakers

Britannica English: Translation of crucial for Arabic Speakers

Comments on crucial

What made you want to look up crucial? Please tell us where you read or heard it (including the quote, if possible).


a flaw that causes the downfall of a hero

Get Word of the Day daily email!

Test Your Vocabulary

Original Meanings Quiz

  • rembrandt-painting-a-young-scholar-and-his-tutor
  • Which of the following is the earliest known sense of the word awe?
True or False

Test your knowledge - and maybe learn something along the way.


Test Your Knowledge - and learn some interesting things along the way.


Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!