Definition one (n.): Old woman's vagina.
Combination of Prune and pOON...yes I know, prune has a 'p' on its own..
Alternate spelling-Prune; Poon and pRUNE...yes I know, prune has a 'p' on its own..
Definition two (n.): Oversexed, or prune-like (like the fruit) pussy. (v.): To oversex, to make a pussy look prune-like.
Definition three (v.): To fuck an old woman, especially in the ass.
Example one: Old Woman
Damn, that's one fine ass proon.
Example two: Old Woman
Guy one: Dude, she's like sixty!
Guy two: Yeah, I have a thing for proon.
Example three: (n.) Oversexed; prune-like pussy.
Random Oversexed Woman: My pussy is sooooo pruned, I can cum on command!
Example four: (v.) To make pussy look prune-like.
Some Guy: I fucked her so hard for so long, that pussy will looked pruned for life.
Example three: Too fuck an old woman, especially in the ass.
Young Woman: You prooned her over prooning me!
Young Man: I'm sorry, yes I prooned her.
Young Woman: But, but...she's a proon!
Old Woman: I may be a proon, but I'm a proon that's getting prooned!
Young Woman: OMGTFBBQ!