When you propel your man meat in a circular motion mimicking that of a helicopter or a windmill. When inertia has reached its apex one
may exert their cosmic dong clock onto un-expecting objects and/or bystanders. Perfected by Willy
Nelson in the late 1980's, this of course inspiring his hit single "whip that
sausage right round."
Slappee: Why does my head hurt?
Slapper: Well my good sir, due to the omega Windmill Dick Slap I had bestowed onto your
forehead, you had slipped into a coma for
27 years 36 days only to be awoken by yet another Windmill Dick Slap to your forehead. And that my friend is why your head hurts.