A [fat chick] or a [fatty] [posse]. Derived from the [fat girl] sorority Omega Mu in the movie [Revenge of the Nerds]. The Omega Mu [plumpers] help the nerds such as [Takashi], [Wormser], [Poindexter], [Lewis and Gilbert], [Lamar Latrell] and [Booger] combat the [jocks] and [cheerleaders] and they put on a [concert] and take control of the campus.
> "Look at that [big fat fatty] in the short skirt and tight, low cut top!"
> "What an Omega Mu!"