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phrase.
refers to an unknown area. the opposite of the common phrase "i know it like the back of my hand". Originates from the fact that most people (unless they are porn actors/models) are quite unfamiliar with the backs of their asses.
Joey: oh look that chick lives in Ismay, Montana. I know that place like the back of my hand. I'll get laid for sure!

Tommy: shit, I know it like the back of my ass.
(walks away defeated...)
by RedDan69 February 02, 2011
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