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fuck buddy

American  

noun

  1. Slang: Vulgar. a person with whom one has a sexual but not a romantic relationship.


fuck buddy British  

noun

  1. taboo a person with whom another person has a relationship based on casual sex only

"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 fuck buddy

First recorded in 1970–75