(adj.) a slang term used to describe sex, in a literal or boasting sense.
ex. 1
Dane: Dude I was so drunk last night and went home with this hotass bitch
Chris: For real? Did you guys have sexual intercourse?
Dane: Not at first, then later on we ended up mashing brakes

ex. 2
Jeff: You and stephanie were so loud last night, were you two doing what I THINK you were doing?
Matt: Yeah man, we were mashing brakes sooo hard.
by GinjerNinjaronimator December 30, 2010
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