crazy

Etymology

From craze + -y.

adj

1. Of unsound mind; insane; demented.
   His ideas were both frightening and crazy.
   Those words appearing to be merely the ravings of superannuation, they were not regarded; but when no other traces of Mary could be found, old Andrew went up to consult this crazy dame once more, but he was not able to bring any such thing to her recollection. 1828, James Hogg, Mary Burnet
   Of all the queer collections of humans outside of a crazy asylum, it seemed to me this sanitarium was the cup winner. […] When you're well enough off so's you don't have to fret about anything but your heft or your diseases you begin to get queer, I suppose. 1913, Joseph C. Lincoln, chapter 5, in Mr. Pratt's Patients
   Grab-a-cop-gun kinda crazy / She's poison but tasty / Yeah, people say "Run, don't walk, away" 2018, Ava Max, Madison Love, Tix, Cook Classics, Cirkut (lyrics and music), “Sweet but Psycho”, in Heaven & Hell, performed by Ava Max
2. Out of control.
   When she gets on the motorcycle she goes crazy.
3. Very excited or enthusiastic.
   The girls were crazy to be introduced to him. 1864, R. B. Kimball, Was He Successful?
   He went crazy when he won.
4. In love; experiencing romantic feelings.
   Why is she so crazy about him?
5. (informal) Very unexpected; wildly surprising.
   The game had a crazy ending.
6. (obsolete) Flawed or damaged; unsound, liable to break apart; ramshackle.
   Buchanan shewed her into a room adjoining to Mr. Steele's dressing-room, and separated from it by a very crazy partition. 1789, John Moore, Zeluco, Valancourt, published 2008, page 203
   They […] got a crazy boat to carry them to the island. 1816, Francis Jeffrey, “Memoirs of Madame de Larochejaquelein”, in The Edinburgh Review February 1816
   Casement windows opened, crazy doors were unbarred, and people came forth shivering—chilled, as yet, by the new sweet air. 1859, Charles Dickens, A Tale of Two Cities
7. (obsolete) Sickly, frail; diseased.
   Over moist and crazy brains. 1663, Samuel Butler, Hudibras
   My poor aunt has often told me […] how long she herself was apprehensive lest my crazy frame, which is now of common shape, should remain for ever crooked and deformed. c. 1793, Edward Gibbon, Memoirs, Penguin, published 1990, page 61

adv

1. (slang) Very, extremely.
   That trick was crazy good.
   I'm flat out. It's crazy stupid here, Kim. 2002, Gina Riley, Jane Turner, That's Unusual: Scripts from Kath and Kim, Series 2, page 67

noun

1. (slang, countable) An insane or eccentric person; a crackpot.
   Allen Gregory DeLongpre: Now drink up, you knuckleheads! Have a blast! It's our night, you crazies! Chloe, where are you? 2011 Allen Gregory, "Pilot" (season 1, episode 1)
2. (slang, uncountable) Eccentric behaviour; lunacy; craziness.
   Then again, her whole evening was full of crazy, and she didn't know what else to do. 2013, Douglas Schwartz, Checkered Scissors, page 211