Half oaf, half buffoon. A boorish loudmouth of limited mental capacity who often embarrasses him/herself.
Dude 1: "Not only does my boss constantly interrupt me, but he also has no fucking clue what he's talking about. His incompetence and stupidity are glaringly apparent to everyone but him. And yesterday when he called me into his office it smelled distinctly of feces."
Dude 2: "Yeah, I heard he recently was elected to the presidency of the local oaffoonery society. He truly elevates idiocy, incompetence, and obnoxiousness to such a profound degree that it's almost an artform."
Dude 1: "What a fucking oaffoon."
Dude 2: "Yup. Pass the blunt?"