1 definition by clay wells

Refering to the effect of when you pull your pants up so high that the inprint of you butt crack becomes visable.
Exp.1.
Damn man that girl needs to pull those booty shorts down yo, she has a major fault line going on!

Exp. 2.
Damn nigga that girl wearin a thin ass dress and a thong, and when she get up she always got a huge ass fault line runnin up her ass!
by clay wells August 1, 2008
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