Definition of Crazy

Adjective: crazy (crazier,craziest) krey-zee

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

Noun: crazy krey-zee
Usage: N. Amer

Someone deranged and possibly dangerous
- loony, looney, nutcase, weirdo, headcase