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1.
Said about a sexually appealing woman, with whom you would be very eager to have sex.

To explain the metaphor: you may be a little too vigorous, and push your penis all the way through her, hence, knocking the back out of her... Obviously not physically possible, but a good, although rather crude, metaphor
Guy A: Phwoar, Check her out, what a stunner!
Guy B: God yeah, I'd knock the back out of that!
by Dr Mox April 07, 2007

Words related to I'd knock the back out of that!

fuckable hott i'd break her pelvis i'd do her i'd tap that phwoar stunner