When you have an itch in your ass.
"Oh i got a bad assrash today"
by Bubba Smith jr September 18, 2006
2 more definitions
Abrasions , pimples, rashes, and bruises on the buttocks.
Unfortunately, the pretty Ukrainian gal had some deal-breaker AssRash
by jiminton October 05, 2013
A real or ficticious condition afflicting a hot-tempered person. Used as an excused for mean-spirited remarks or action.
Watch out for Ken...he's got an ass rash and is gonna be hard to get along with today.
by Harry Flashman August 31, 2004