biff twiffer Share definition Flag A person who takes a bath, farts in the bathtub, then bites the bubbles created from said fart. Johnny's always smells like ass, he must be a biff twiffer. biff twiffer by BigRock June 20, 2009 0 0 Get merch Get the biff twiffer mug. Buy Now — $32.95 See more merch