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

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

From BBC • Oct. 4, 2025

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

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

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