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English definition of “crazy”

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crazy

adjective uk   /ˈkreɪ.zi/ us  

crazy adjective (NOT SENSIBLE)

A2 stupid or not reasonable: It's a crazy idea. You're crazy to buy a house without seeing it. mentally ill: I seriously think she'll go crazy if she doesn't have a holiday soon.
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crazy adjective (ANGRY)

B2 annoyed or angry: The constant noise drove me crazy (= made me become angry).
crazily
adverb uk   /-zɪ.li/ us  
craziness
noun [U] uk   /-nəs/ us  

crazy

noun [C] uk   /ˈkreɪ.zi/ US slang us  
a person who behaves in a way that is stupid or not reasonable, especially one who is mentally ill: There's some old crazy over there shouting and spitting at people.
(Definition of crazy from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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