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

As Ma performed in the park, Gonzalez stood in the river basin, spray-painting in neon-pink blockbuster letters the name of his organization, East Side of the River, onto pillars under Slauson Avenue.

From Los Angeles Times ● Jul. 13, 2026

Moldova imposed a 15-day state of alert in the Dniester river basin on Monday as a precaution.

From BBC ● Mar. 17, 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

Areas in the Weser river basin, that was only mildly affected in 1993, for example, would have experienced floods greater than the 100-year flood.

From Science Daily ● Mar. 27, 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