Proper noun
(dated, geography) Southern Germany, the high-lying land of the German people in Central Europe around the Alps.
(dated, linguistics) those areas where High German is traditionally spoken, i.e. central Germany, southern Germany, Austria, Switzerland, South Tyrol, Alsace, Luxembourg, eastern Belgium, and south-eastern Limburg (Netherlands); at various historic times including different, often wider, territories.
Source: en.wiktionary.org