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

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

From BBC • Mar. 17, 2026

They say "Yana" - who has been named after the river basin where she was discovered - is the world's best-preserved mammoth carcass.

From BBC • Dec. 23, 2024

“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

This is because every river basin has its own special features.

From Science Daily • Mar. 27, 2024

Planting their orchards for millennia, the first Amazonians slowly transformed large swaths of the river basin into something more pleasing to human beings.

From "1491" by Charles C. Mann