Diarrhea that is so water-like, it feels as if you are pissing out your asshole.
Damn, I had those 12 Chalupas, now I have a bad case of butt pee or ass piss.
by Big-Z™ October 17, 2005
1 more definition
All that comes out of your ass after a night of ingesting large amounts of Buttwieser.
I got off the toilet after an hour and all that came out was butt pee.
by you know my fuckin name! June 19, 2003