plus-one
n.— «But Slive previously has said he’s open to discussing the possibility of what’s known as a “plus-one” format, whereby the top two teams after the traditional bowls are over would meet in a one-game championship matchup.» —“BCS official says playoff isn’t in future, ‘plus-one’ could be” by Jack Carey USA Today Nov. 28, 2007. (source: Double-Tongued Dictionary)