A term describing a person, event or thing with no redeeming qualities that still manages to become really famous or popular (usually for no good reason at all). Derived from combining the words "fail" and "phenomenon."
Girl: "I'm going to watch the new Madea tonight!! Wanna come?"
Guy: "I'd rather gouge my eyes out than support the Tyler Perry failnomenon. No thanks."
Everyone thought Obama was gonna bring hope, but he turned out to be the biggest failnomenon since the Backstreet Boys.