baggy sac
A sac that has a sag coefficient of AT LEAST .09. Typically hanging a generous 5 inches below the head. the hypotenuse from "tip to tail" can be found by squaring the shaft and adding to the square of the sag times its sag coefficient. Gross.
Wow. Did you happen to pee next to Jerry today? I swear I saw his baggy sac droop outside his fly when he was done! mmmmmm gross.