by Josh123456789 March 25, 2007
Double penetration sex, with one man fucking the girl in her vagina in and the other in the ass. They alternate thrusts to create a piston action, much like that of an engine.
by Color Rot January 07, 2009
n. A sexual maneuver between a man and a woman/pwn victim/Pruger in which the man retracts his testicles up into his lower stomach and then shoots out one testicle at a time, alternating testicles with each blast. This is an alternative form of The Shotgun.
The NBA team The Detroit Pistons got its name because the founder of the franchise could use The Piston with extreme speed and accuracy.
by MC Derf March 17, 2008
A Sexual act similar to cave diving. The male not only sticks his head in the woman's vagina, but proceeds to climb entirely inside of her. Once inside of her he sticks his penis out of her vagina. Using his penis the girl goes and engages in intercourse with someone else. (The only downfall to this act is that a cesarean section will need to be performed in order for the guy to come out.)
Friend 1: Did you hear about Jessica?
Friend 2:No what happened?
Friend1: Her and Jack did the piston!
Friend 2:No what happened?
Friend1: Her and Jack did the piston!
by The Pistonator September 04, 2014
n. A sexual maneuver between a man and a woman in which the man retracts his testicles up into his lower stomach and then shoots out one testicle at a time, alternating testicle with each blast. This is an alternative form of The Shotgun.
The NBA team The Detroit Pistons got its name because the founder of the franchise could use The Piston with extreme speed and accuracy.
by MC Derf March 17, 2008