The concoction of stale, warm beer and watered down ice from the container you had the keg sitting in. Keg juice is what gets on your clothes when carrying a keg to your car for return to the store.
Person 1: I'm gonna return the keg

(Person 1 removes the tap and picks up the keg from the trashcan it was sitting in and it's dripping with watery keg juice)

Person 2: Ohh man! That's nasty dude!

Person: Noooo keg juice all over the clothes. Damn it!!!
by Kyle N. September 2, 2008
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