Top definition
During insertion, when a woman uses her extrordinarily muscular labias to pincer-off a man's penis. What is left is a bloody nub inside vagina and a fountain of blood gushing from the mangled, chewed-up strotum.

Common to female weight lifters and black chicks.
Damn, that bitch gave me a power clam and now i'm growing tits.
by JJ January 23, 2004
Get the mug
Get a Power Clam mug for your barber Bob.