clobber-knocker
A quick strike to the top of the head with the hand. The clobber-knocker is applied by clenching the fist and swinging down on top of the head, using only the flat part of the fingers between the first and second knuckles. It is a very practical form of a sucker punch.
Brendan was pissing me off one day, so I gave him a clobber-knocker to show him how I felt.
clobber-cock knockers
A game where large-breasted women take turns slapping a guy's dick with their boobs. Each slap needs to be harder than the last. The game lasts until either the guy comes (he wins) or someone breaks his dick (she wins). Very dangerous.
I left the party because a game of clobber-cock knockers was starting up, and I didn't want to be there for that shit.