Invented in Harvey, New Brunswick, Canada. A form of self-gratification whereby one's fist is inserted into one's rectum. Once fully inserted past the wrist one attempts to fully open the hand and extend all digits. When performed with a partner this is known as the Harvey Hand Grenade.
Due to an increase in medical expenses the Harvey High Five is now forbidden in all New Brunswick Prisons.
by Noisy as Dry Buggery October 4, 2010