look up any word, like cunt:
Phrase used in pretty much every conceivable scenario when person#1 makes a claim that requires proof to be believed, and person#2 demands that the proof be given, or person#1 shuts the fuck up.
Pietro, Ultra, Earl Grey: Hey! That's not fair ACM! "proof or stfu" is our phrase that we invented!
The ACM: proof or stfu
by The A-C M December 16, 2006

Words related to proof or stfu

chav forum n00b proof stfu