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soixante-neuf

American  
[swah-sahnt-nurf, -nuhf, swa-sahnt-nœf] / ˌswɑ sɑntˈnɜrf, -ˈnʌf, swa sɑ̃tˈnœf /

noun

  1. sixty-nine.


soixante-neuf British  
/ swasɑ̃tnœf /

noun

  1. Also: sixty-nine.  a sexual activity in which two people simultaneously stimulate each other's genitalia with their mouths

"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 soixante-neuf

Borrowed into English from French around 1915–20