Verb, -to hit someone upside the head preferably with a a dead body(or cadaver).
Joe Schmo: 'Wow, you're acting like fucking idiot, i'll be cadavering you in about 5 seconds if you don't shut the fuck up.'
Similar to planking, cadavering is a practical joke involving acting dead in a public place.
"Oh my gosh, is he dead?" "No, he's just cadavering."