A measure of time one is likely to be away from a task at hand, equal to that commonly allocated to the act of masturbating
Luke: Where are you going?
Ryan: I'm off to some guy's place from craigslist to j/o in his model train room, I'll be back in a jizzy.
Luke: Can you bring back some crab meat?
Ryan: Is imitation ok?
Luke: Fo shizzle!