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

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

"Due to the unique mechanism of oasis formation, a river basin often nurtures multiple oases across several countries, making transboundary cooperation key to addressing water scarcity and promoting sustainable development," he said.

From Science Daily • Apr. 22, 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