Use the adjective crazy to describe actions that aren't sensible, like the crazy way your brothers run around the house when their favorite team wins a game.

Crazy can also mean "insane," though in today's world, it is offensive to apply it to those who struggle with mental illness. Instead, stick with using crazy to describe temporary and more light-hearted situations like being crazy about a new boyfriend or girlfriend or going "football crazy" during the Super Bowl.

Definitions of crazy
  1. adjective
    affected with madness or insanity
    synonyms: brainsick, demented, disturbed, mad, sick, unbalanced, unhinged
    afflicted with or characteristic of mental derangement
  2. adjective
    foolish; totally unsound
    “a crazy scheme”
    synonyms: half-baked, screwball, softheaded
    not practical; not workable or not given to practical matters
  3. noun
    someone deranged and possibly dangerous
    synonyms: looney, loony, nutcase, weirdo
    see moresee less
    type of:
    lunatic, madman, maniac
    an insane person
  4. adjective
    intensely enthusiastic about or preoccupied with
    crazy about cars and racing”
    synonyms: dotty, gaga, wild
    enthusiastic, keen
    having or showing great excitement and interest
  5. adjective
    possessed by inordinate excitement
    “the crowd went crazy
    “was crazy to try his new bicycle”
    in an aroused state
  6. adjective
    bizarre or fantastic
    “had a crazy dream”
    “wore a crazy hat”
    strange, unusual
    being definitely out of the ordinary and unexpected; slightly odd or even a bit weird
Word Family

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