A prank, prevalent in college dorm rooms, in which the prankster urinates into a disc (such as a plate or frisbee) and freezes it in his/her refrigerator. After the urine is frozen, the perpetrator carefully removes the frozen disc from the container and slides it underneath a victims door. The piss subsequently melts and leaves a gargantuan mess.
"Dude, I heard Joey egged your car last night!"
"It's okay, I'm going to hit him with a piss disc later."
Nickname given to bales of marijuana thrown overboard or out of airplanes. Origin is reportedly from members of the US Coast Guard in the area of Southern Florida.
"Base we've got some square groupers floating outside of Miami harbor."