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1. Affected with madness or insanity
   "a man who had gone crazy";
   - brainsick, demented, disturbed, mad, sick, unbalanced, unhinged
    
2. Foolish; totally unsound
   "a crazy scheme";
   - half-baked [informal], screwball [informal], softheaded, wiggy [US, informal], crackpot [informal], nutty [informal]
    
3. Possessed by inordinate excitement
   "the crowd went crazy"; "was crazy to try his new bicycle"
    
4. Bizarre or fantastic
   "had a crazy dream"; "wore a crazy hat"
    
5. Intensely enthusiastic about or preoccupied with
   "crazy about cars and racing";
   - wild, dotty [informal], gaga [informal]

1. An insane person
   - lunatic, madman, maniac, loony [informal], looney [informal], nutcase [informal], headcase [informal]

Derived forms: crazies, crazier, craziest

See also: basket case [informal], enthusiastic, excited, fruitcake [informal], impractical, insane, keen, mentalist [Brit, informal], nutbar [N. Amer, informal], nutcake [US, informal], nutjob [informal], nutter [Brit, informal], oddball, strange, unusual, wackadoodle [N. Amer, informal], wackjob [N. Amer, informal], wacko [informal], whackjob [N. Amer, informal], whacko [informal]

Type of: diseased person, sick person, sufferer

Encyclopedia: Crazy, Sick & Cracked