When something is so nasty you just want to slap it. Most commonly used as an adjective.
Boy: "I want to eat your FUP for dinner"
Girl: "You're so slap nasty"
4👍 4👎
a insult to someone meaning that they are a discusting, vd filled, whore
" Man I brought home a SLAP NASTY HOE last night and now my ball itch
5👍 7👎
Basicly any sexual act. Normally used when the sexual act isn't clear.
I heard him and Kate slapping the nasty last night
Damn, you're sweaty, have you been slapping the nasty?
He likes to slap the nasty with cherry-flavored lubricant.
10👍 2👎