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asshole

American  
[as-hohl] / ˈæsˌhoʊl /

noun

Vulgar.
  1. anus.

  2. Slang.

    1. a stupid, mean, or contemptible person.

    2. the worst part of a place or thing.


adjective

  1. Slang. stupid, mean, or contemptible.

asshole British  
/ ˈæsˌhəʊl /

noun

  1. slang the arsehole See arse

"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

Etymology

Origin of asshole

1350–1400; Middle English arshole anus; ass 2, hole