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

That includes the upper Indus river basin, which serves parts of China, India, Pakistan, and Afghanistan.

From BBC • Oct. 4, 2025

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

Among other things, the researchers looked at the climate moisture index, the soil texture, the forest cover, the size of the river basin, and the river gradient.

From Science Daily • Mar. 27, 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