Scottish dialect form of "pissing". Basically means "urinating".
Dave was pishing up the wall.
by Rabsputin September 03, 2011
A sexual fetish related to urinating on one another during foreplay and sex.
Pishing is a fetish in which while performing oral sex, the participants stop and the female will pee on the other. Generally "playing" in and with the urine.
by cannavibe May 14, 2011