river basin

American  

noun

Physical Geography.

1. the area of land drained by a river and its branches.

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river basin Scientific  

1. 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.

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Etymology

Origin of river basin

First recorded in 1875–80

Example Sentences

See Examples For:

river basin

"A river basin is fed by water upstream, often in another country," she pointed out.

From Barron's ● Sep. 17, 2026

North Wales and the Upper Severn river basin entered drought conditions last week, Natural Resources Wales said.

From BBC ● Jul. 29, 2026

The trailhead starts at San Pascual Stables and journeys along the concrete river basin, with a few short trails that veer off from the main path.

From Los Angeles Times ● May 30, 2024

Focus has shifted to the two rivers after flooding in the Ural river basin devastated a swathe of Russian and Kazakh territory further west last week.

From BBC ● Apr. 16, 2024

In an ecological version of therapeutic nihilism, they want to leave the river basin to its own devices.

From "1491" by Charles C. Mann