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

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 Navajo Nation has one of the largest single outstanding claims in the Colorado River basin and will vote soon on the measure in a special session.

From Seattle Times • May 13, 2024

In March, there was excitement when one steelhead was spotted in the Santa Ynez River basin in Santa Barbara County.

From Los Angeles Times • Apr. 29, 2024

Much of it, including the greater part of the Amazon River basin, is unfit for the growth of food-stuffs.

From Commercial Geography A Book for High Schools, Commercial Courses, and Business Colleges by Redway, Jacques W. (Jacques Wardlaw)