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

Texas' Colorado River basin narrowly meets the threshold at 103,300 square kilometers.

From Science Daily • Dec. 31, 2025

Its sandy soils have a low capacity for retaining water and a poor level of organic matter, as does the rest of the Congo River basin, according to the FAO.

From Barron's • Nov. 26, 2025

The towns speckling the Columbia River basin have long ridden the ebbs and flows of far-off markets: volatile crop prices, changes in the livestock trade, pressure on the lumber industry.

From The Wall Street Journal • Nov. 4, 2025

The service forecast moderate to major river flooding in central Florida and the St. Johns River basin over the weekend and through the coming weeks.

From Los Angeles Times • Oct. 11, 2024

This condition was in considerable contrast to the great spongy masses I had noted in the Tazin River basin, between Athabaska and Great Slave lakes, in 1914.

From The Barren Ground Caribou of Keewatin by Harper, Francis