A fool, a loser, the dumbest of all dummies. A playful term used to describe someone who is being an idiot, or not making sense.
"What the fuck does that mean you poon toon?"
A playful term used to describe someone who is behaving in a silly, stupid, idiotic, or dumb manner that doesn't make sense to anyone else.
"What the fuck are you talking about you poon toon?"