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1.
The horizontal crack formed between a womans butt and her upper leg. Usually, this crack is found in latino, or african women. A pseudo crack can be created when a woman is wearing pants that create the allusion of a HBC.
Jennifer Lopez, sumo wrestlers. Used in speech: "Dude, she has no boobs, but did you see her Horizontal Butt Crack"
by riversabound October 17, 2010