motherfucker Share definition Flag One who yawns with his (or her) jaws wide open, to the extent you can diagnose tonsillitis from the other side of the room. "I am so bored by sitting in this VIP lounge, I am yawning like a motherfucker bro!" motherfucker by pogopogo May 20, 2010 0 0 Get merch Get the motherfucker mug. Buy Now — $32.95 See more merch