Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “crazy”

See all translations

crazy

adjective  /ˈkreɪ·zi/ us  
very strange or foolish: She’s the craziest person I’ve ever met. [+ to infinitive] You’re crazy to rent the place without seeing it first. Crazy can mean mentally ill. Crazy can also mean behaving in a strange way esp. because of stress, as if you are mentally ill: The constant whine of the machine nearly drove (= made) me crazy. I think she’ll go (= become) crazy if she doesn’t take a vacation soon.
crazily
adverb [not gradable]  /ˈkreɪ·zə·li/ us  
craziness
noun [U]  /ˈkreɪ·zi·nəs/ us  

crazy

noun [C usually pl]  /ˈkreɪ·zi/ infml us  
a person who acts in a strange or threatening way, esp. one who is mentally ill: Are we talking about a bunch of crazies or about a legitimate military force?
(Definition of crazy from the Cambridge Academic Content Dictionary © Cambridge University Press)
What is the pronunciation of crazy?
Add Cambridge dictionaries to your browser to your website

“crazy” in American English

Definitions of “crazy” in other dictionaries

Word of the Day

luck out

to be very lucky

Word of the Day

Think long and hard; the language of decisions

by Liz Walter,
January 28, 2015
One of the best ways (perhaps the best way) to improve your English is to learn how words go together in phrases, idioms, or other patterns such as verb/noun or adjective/noun pairs (often called ‘collocations’). This blog looks at some useful phrases and collocations connected with the subject of decisions, something we

Read More 

micro pig noun

January 26, 2015
an extremely small pig, bred to be a pet Micro pigs have become popular pets recently, with famous owners including Victoria Beckham, Paris Hilton and Olympic diver, Tom Daley.

Read More