Jack Off

To masturbate; the stimulation of a male's penis until orgasm is achieved and ejaculation occurs.

Jill didn't want to have sex right now, so Jack decided to jack off.

by Phillip Knowles January 19, 2006

Jack Ass

A person who is so damn ignorant that the things they do cause you and your friends to laugh even though it causes them Pain.

Can you believe that Jim shot himself in the foot, What a JACK ASS

by Dilligaf1971 October 20, 2007

jack pack

The man purse Jack Bauer uses in 24 Season 5.

Look at the Jack Pack! I want one!

by Vanessa April 27, 2006

Jack's Mannequin

The perfect shade of "dark blue." Which may or may not be found in a box of crayons.

Oh, would you look at that? Tonight's the prefect shade of Jack's Mannequin.

by Kerosene July 26, 2008

Jack Knob

a moron, Jack ass ,door knob, fool

Dude, you put the key in the IGNITION Jack Knob

by LSULSUJOE October 25, 2006

air jack

the hand gesture associated with actual jacking off; like air guitar only air jacking off

jake and i simultaniously air jacked all over levi's face and gave him an air facial.

by cheweysmoker October 5, 2008

Jack Spicer

An evil boy genius from the excellent Y-7-rated cartoon Xiaolin Showdown. He invents different kinds of useless attack robots and is highly failure-prone and -phobic. Looks kinda Goth.

That Jack Spicer's a bumbling, Goth-lookin' evil boy genius.

by 'Annony' June 7, 2005