A Roman emperor, one of many known as "The Barracks Emperors" which was a series of emperors who ascended to the throne by staging military coups, and ruled for a short time before themselves being deposed. Pupienus in particular ruled for roughly 2 months from February to May 238 a.d.

His fuckin' name sounds like Poopy Anus, man. Best emperor ever.
Guy #1: Dude I just shat, i have a Pupienus.
Guy #2: You mean you have a fairly insignificant Roman emperor?
Guy #1: Yeah.
by Schlong McFondle April 28, 2007
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