piss denial

The act of not letting yourself piss when you desperately need to; a test of sheer will.

person 1: Oh my god I really need to piss.
person 2: The bathroom's down the hall man.
person 1: Oh no thanks, I'm trying out piss denial. I've been holding it in since this morning. The pain is excruciating but I gotta make it until at least the end of the night.
person 2: Dude, what the fuck?