savanna, savannah:An open plain of long grass, frequently with scattered drought-resistant trees, which is characteristic of certain tropical and subtropical regions with distinct wet and dry seasons (in early use esp. with reference to tropical America). Also: the grassland or vegetation of such a plain. Also fig. ——Oxford English Dictionary

savanna, savannah:a large flat area of grassy land, especially in Africa.——Longman Dictionary of Contemporary English  @en