The act of going to the bathroom sitting down , and after taking a piss you take a dump and the dump makes a splash so big that piss splashes back onto (and in some cases inside) your ass
Definition: piss ass (verb)
getting piss on (or in) your ass after taking a large shit.
Last night i took a dump so big i gave myself piss ass , worst feeling ever
A word of expression , used primarily when in someone in a video game or funny video l gets hit with something or explodes in a forceful way.
Damn that explosion was wild ! dude got skablounched!