The process of taking someone's bare ass and a tennis racket. Pressing the tennis racket up to their bare cheeks hard, and then taking a wire brush (like a grill brush) and rubbing it vigorously back and forth on the tennis racket.
That guy deserves a wafflebutting for what he did.
"Wafflebutt" is a pejoritive directed at cops in general, and motorcycle cops in particular.
This definition is based on the impression left on the gabardine pants worn by motorcyle cops from the criss-cross pattern on their bike saddles, and implies laziness based on the duration required to impress the pattern on their butts.
This definition prevailed in the '70s and before.