Peeing in a urinal or a toilet from the side instead of from the front. Analogous to a basketball player shooting a jump shot from the baseline rather than from the top of the key.
Jamanthony: One sec Reece, I'm bout to take a baseline piss.
Shareece: Who the fuck you think you are b? Shane Battier?
Jamanthony: He got two rings. How many you got Reece?
Shareece: Damn cuz you got me, ok go ahead...
by xjamanthonyx September 13, 2013
Get the baseline piss mug.