An attractive female, usually considered out of your league.
"Yo man, see that banging girl over there at the bar? I'm gonna go hit that up."
"Good luck man, but that's moonpoon. Your fugly ass doesn't have a chance."
Pussy that can be seen when a girl has mooned you
Guy1:Did you see the ass on that girl that just mooned us?
Guy2:Naw man I was too busy starring at that moonpoon