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

Samples were collected near the Santa Maria da Serra dam, close to the Barra Bonita reservoir, where contaminants from across the river basin tend to gather.

From Science Daily ● Mar. 21, 2026

“We know now,” Wilkerson said, “that the river basin downtown has a high groundwater table and a really granular type of soil, so there’s a zone in this downtown region where liquefaction is a potential.”

From Los Angeles Times ● Aug. 27, 2024

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

Neighbouring Kiambu county, parts of which are on a river basin and have been affected by the floods, has also announced it will take measures to mitigate the situation, including building inspections.

From BBC ● Apr. 29, 2024

On a plateau commanding the Coatzacoalcos river basin, San Lorenzo proper was inhabited mainly by the elite; everyone else lived in the farm villages around it.

From "1491" by Charles C. Mann