|the entire geographical area drained by a river and its tributaries; an area characterized by all runoff being conveyed to the same outlet; "flood control in the Missouri basin" [syn: river basin]|
area from which all precipitation flows to a single stream or set of streams. For example, the total area drained by the Mississippi River constitutes its drainage basin, whereas that part of the Mississippi River drained by the Ohio River is the Ohio's drainage basin. The boundary between drainage basins is a drainage divide: all the precipitation on opposite sides of a drainage divide will flow into different drainage basins.
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