A "Jack Dempsey" refers to one beating his meat very aggressively, as the legendary boxer Jack Dempsey flogged his opponents.
Dude, I got so excited over that midget porn I was watching that I stole some face cream from my sister's make-up bag and gave myself a "Jack Dempsey". Now my pecker is sore.
by Midnight Stroker July 24, 2008
Can you define these popular missing words?