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

"A river basin is fed by water upstream, often in another country," she pointed out.

From Barron's ● Sep. 17, 2026

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

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

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

Project number one: we’ll be making a relief map of the Tigris and Euphrates river basin.

From "Merci Suárez Changes Gears" by Meg Medina