over-hang
n.— «It is a surprise to many people that in the coming three years, there is a very good possibility that there might be more than 120 MPs in Parliament. A Parliamentary “over-hang,” as it is called, is caused by the way MMP calculates how many seats a party gets in Parliament.» —“Maxim Real Issues No. 171″ Scoop (New Zealand) Aug. 26, 2005. (source: Double-Tongued Dictionary)