noun, Physical Geography.
the area of land drained by a river and its branches.
The land area that is drained by a river and its tributaries. The Mississippi River basin, for example, is a vast area that covers much of the central United States from the central ranges of the Appalachian Mountains in the east to the eastern ranges of the Rocky Mountains in the west, funneling toward its delta in southern Louisiana and emptying into the Gulf of Mexico.
noun 1. the channel in which a river flows or formerly flowed.
noun 1. a tree, Betula nigra, of the eastern U.S., having papery, reddish-brown bark that peels away.
noun, Pathology. 1. onchocerciasis. river blindness noun 1. another name for onchocerciasis river blindness riv·er blindness (rĭv’ər) n. See onchocerciasis.
noun 1. any shallow-draft boat used on rivers.