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Synonyms

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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. )

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.

Every side is still within a chance so points difference could be crucial.

From BBC

More than 25 years in the making, supporters see the deal as crucial to boost exports, support the continent's ailing economy and foster diplomatic ties at a time of global uncertainty.

From Barron's

This difference turns out to be crucial when modeling the large-scale behavior of the universe.

From Science Daily

Within these refuges, jawed vertebrates appear to have held a crucial advantage.

From Science Daily

Billionaires who hadn’t already established residency elsewhere by Jan. 1 this year have missed a crucial deadline.

From Los Angeles Times