A term used to describe to the act of female masturbation. Useful as a delicate description or an obscene insult. Perhaps derived from the male version of "whack" off.
by JB February 27, 2005
Slang for Jack in the Box.
by G. Thomas July 26, 2006
The act of thrusting the man junk so far into a woman's (or man's if you are homosexual) anus multiple times that the balls consistently slap against the "host's" butt cheeks making a sound like a great high five.
KirtKanReed: "i am soo hungover bro, i can't remember anything about last night."
ChadKant: "you wouldn't want to."
Zenovia's Playa: " YEAH! BECAUSE CHAD GAVE YOU THE sack whack on the back crack WHILE YOU WERE SHIT FACED DRUNK LAST NIGHT AND PASSED OUT ON THE COUCH!"
ChadKant: "you wouldn't want to."
Zenovia's Playa: " YEAH! BECAUSE CHAD GAVE YOU THE sack whack on the back crack WHILE YOU WERE SHIT FACED DRUNK LAST NIGHT AND PASSED OUT ON THE COUCH!"
by Zenovia's Playa June 14, 2009