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crucial

adj.
US //ˈkɹuʃəɫ// UK //kɹˈuːʃəl// cru·cial
  1. 1 extremely important (adj.)
    B2 Upper Intermediate Academic General-service

    extremely important because it will affect the final result of something.

    essential or decisive for determining the outcome or future of a situation; vital to success.

    Example

    The goalkeeper made a crucial save in the final minute of the game.

    Example

    The research team reached a crucial stage in the experiment where any minor error could invalidate months of data collection.

    Usage

    Often followed by the prepositions 'to' or 'for'.
    Pitfall
    This is more crucial than that.
    This is more important than that.

    While common in speech, 'crucial' is often considered a non-gradable adjective in formal writing; something is either crucial or it is not.

  2. 2 excellent (adj.)
    C1 Advanced Slang Informal Dialect Music

    very good or excellent, especially when talking about music.

    a slang term of approval meaning excellent or of high quality; historically associated with reggae culture.

    Example

    That new track they played last night was absolutely crucial.

    Example

    The DJ was known for spinning crucial reggae cuts that you couldn't hear anywhere else in the city.

    Teacher's tip

    This usage is specific to certain dialects and subcultures, particularly in Jamaican English; learners should use 'essential' in most other contexts.
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  1. 3 cross-shaped (adj.)
    C2 Proficiency Archaic Technical Science

    shaped like a cross.

    having the form of a cross; cruciform.

    Example

    The botanist noted the crucial arrangement of the petals on the rare flower.

    Example

    The ancient structure was built upon a crucial ground plan, with four wings extending from a central hub.

    Usage

    In modern English, 'cruciform' is almost always preferred for this meaning.
    • cruciform
    • cross shaped
Origin

1706, from French crucial, a medical term for ligaments of the knee (which cross each other), from Latin crux, crucis (“cross”) (English crux), from the Proto-Indo-European *(s)ker- (“to turn, to bend”). The meaning “decisive, critical” is extended from a logical term, Instantias Crucis, adopted by Francis Bacon in his influential Novum Organum (1620); the notion is of cross fingerboard signposts at forking roads, thus a requirement to choose.

Word family

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