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anal intercourse

American  
[eyn-l in-ter-kawrs] / ˈeɪn l ˈɪn tərˌkɔrs /

noun

  1. a form of sexual activity in which the anus is penetrated, especially by a man’s penis.


anal intercourse British  

noun

  1. a form of sexual intercourse in which the penis is inserted into the anus

"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 anal intercourse

First recorded in 1885–90