jackpack
n. The bag in which Jack Bauer carries his gun, PDA, ammo, cell phone, duct tape, knife, scope, etc. It is NOT a man purse.
The terrorists thought they had Bauer at last, but he pulled a bazooka out of his jackpack.
JackPack
A masturbation kit consisting of tissues and lotion.
"I need to stop by Target on the way home and grab a JackPack.
jackpacking
When travelling with nothing but the clothes on your back and whatever can fit in your jacket.
I'm going jackpacking this weekend, so i won't be bringing any luggage