What is "limagne"

The Limagne is large plain in the Auvergne region of France in the valley of the Allier river, on the edge of the Massif Central. It lies entirely within the département of Puy de Dôme. The term is sometimes used to include this, and three other less extensive plains, that lie along the valley of the Allier, in which case the first is known as Grande Limagne to distinguish it from the others. The name is derived from the Latin Lacus Magnus, or large lake.