When you have sex with a girl (smash) and then shit talk her behind her back (trash). Generally only done by douches.
Person 1- Dude, that chick Ruby is a total buster.
Person 2- Didn't you nail her?
Person 1- Of course. It's the classic "smash n trash".
Person 2- Dooooooooouche.
by poony mctang July 12, 2010
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