One who cuts off his own penis and smacks people with it.
Get that thing out of my face and quit being such a knob knocker.
by Shadowstone May 13, 2010
A simple game for men in which they place each hand at opposite sides of their navel area, and bat their penis back and forth in succession in order to get as many knocks as possible. In order for competitive play, one hand can be substituted for another persons hand.
Lets play knob knockers Will, for it's a grand game!
by clydeplayer April 26, 2011