Pronunciation: (zär, sär),[key] —n. 1. Also called Saar' Ba'sin. a coal-producing region in W Germany, in the Saar River valley: governed by the League of Nations 1919–35; returned to Germany 1935 as a result of a plebiscite; under French economic control following World War II until 1956.
2. French, Sarre. a river in W Europe, flowing N from the Vosges Mountains in NE France to the Moselle River in W Germany. 150 mi. (240 km) long.