A slam sack is a body used for fucking. This usually refers to females, but has come to encompass anyone who fits the description.
David: I am heading out to the bar to hopefully find a chick for tonight.
Kate: Are you looking for a girlfriend?
David: Nah, just looking for a slam sack.
Kate: Are you looking for a girlfriend?
David: Nah, just looking for a slam sack.
by cuppkatee December 6, 2015
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