Twilf Ask Urban Dictionary about Twilf Share definition Flag n. One who farts in the bathtub and bites the bubbles. v. His favorite pastime is twilfing. He may be incompetant, but at least he is a world class Twilfer. Twilf by Anthony A. Aardvark September 29, 2006 0 0 Twilf Merch Get the Twilf mug. Buy Now — $32.95 See more merch