Knob Swallower Share definition Flag Someone who really pisses you off. Undertakes homo activites. Adam: "Jonny shagged Paul's missus last night!"Steve: "He's a fuckin' knob Swallower!" Knob Swallower by BallBagBob September 7, 2009 0 0 Get merch Get the Knob Swallower mug. Buy Now — $32.95 See more merch