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.

Definitions of crucial
  1. adjective
    of extreme importance; vital to the resolution of a crisis
    “a crucial moment in his career”
    “a crucial election”
    “a crucial issue for women”
    synonyms: important
    being in or verging on a state of crisis or emergency
    critical, decisive
    forming or having the nature of a turning point or crisis
    life-and-death, life-or-death
    vitally important
    pivotal, polar
    being of crucial importance
    determining or having the power to determine an outcome
    basic and fundamental
    see moresee less
    of little importance; not decisive
  2. adjective
    of the greatest importance
    crucial information”
    synonyms: all important, all-important, essential, of the essence
    important, of import
    of great significance or value
  3. adjective
    having crucial relevance
    crucial to the case”
    directly relevant to a matter especially a law case
Word Family

Test prep from the experts

Boost your test score with programs developed by’s experts.

  • Proven methods: Learn faster, remember longer with our scientific approach.
  • Personalized plan: We customize your experience to maximize your learning.
  • Strategic studying: Focus on the words that are most crucial for success.


  • Number of words: 500+
  • Duration: 8 weeks or less
  • Time: 1 hour / week


  • Number of words: 500+
  • Duration: 10 weeks or less
  • Time: 1 hour / week


  • Number of words: 700+
  • Duration: 10 weeks
  • Time: 1 hour / week