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

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

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

From BBC • Oct. 4, 2025

Of the more than one dozen glacial lake outburst incidents recorded in Nepal in the past 50 years, four have been in the Everest’s Dudhkosi river basin.

From BBC • Aug. 20, 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

Constrained by its punishing climate, poor soil, and lack of protein, these scientists argue, large-scale societies have never existed—can never exist—in the river basin.

From "1491" by Charles C. Mann