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camel toe

British  

noun

  1. slang the visual effect created when a woman's trousers cling too tightly to the crotch, emphasizing the shape of the pudenda

"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 camel toe

C20: from the alleged similarity between this effect and the shape of a camel's toes