It means stupid, you know the word Moron? Well its that but spelt wrong
That hipster kid with the fake Ray-Bans is a right Mooron!
1. A person of lesser intelligence who believes the lies produced by Michael Moore.
2. A person who bases there political views off what they heard from Michael Moore and other left wing idiots.
See also socialist.
Dick: "Did you hear what that guy said about the president?"
George: "Yeh he is such a mooron."