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Synonyms

crap out

British  

verb

  1. slang to make a losing throw in craps

  2. slang to fail; withdraw

  3. slang to rest

  4. slang to fail to do or attempt something through fear

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

crap out Idioms  
  1. Back down, quit, When it got to the point of putting up some money, Jack crapped out . This expression originated in the game of craps, where it means to make a first throw (of the dice) of two, three, or twelve, thereby losing. [ Slang ; 1920s]

  2. Go to sleep. This usage was military slang for sleeping during work hours or during a crap game. [ Slang ; c. 1940]

  3. Die, as in He's really sick; he could crap out any time . This usage is less common than def. 1 or def. 2. [ Slang ; 1920s]