Apparently means to tell off/ make fun of someone, but has been over used to the degree where its as appealing as having a one night stand with Whoppi Goldberg.
Actually, one would prefer to have that one night stand with her after attempting to say the word.
Loser from Brockton*: Oh you rashed! U heard dat???
Guy from Brooklyn: if you don't shut the fuck up, you'll wish you had a rash instead of what I'm gonna do yo ya face.
Guy from Philadelphia: Then I'll smash it in with Bricks
Guy from Compton: You don't even want me to describe the graphic detail of my participation.
Chick from Canada: And then we'll all start to get serious, and proceed beat you down.
*This town was picked because unfortunately, I live here. feel free to mad lib it
guy 2: No dude, he's a RASH.
Guy 2: Sure.
Rash : Cool, when are we meeting?
Guys 1 & 2 : Fucking rash.
"In a moment of rashness I cut off my nose"
"Mate, I just drank four bottles of bleach!"