watershed

American  

[waw-ter-shed, wot-er-] / ˈwɔ tərˌʃɛd, ˈwɒt ər- /

noun

• watersheds
  plural

1. Chiefly British. the ridge or crest line dividing two drainage areas; water parting; divide.

2. the region or area drained by a river, stream, etc.; drainage area.

3. Architecture. wash.

4. an important point of division or transition between two phases, conditions, etc..

   The treaty to ban war in space may prove to be one of history's great watersheds.

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adjective

1. constituting a watershed.

   a watershed area; a watershed case.

watershed British  

/ ˈwɔːtəˌʃɛd /

noun

1. the dividing line between two adjacent river systems, such as a ridge

2. an important period or factor that serves as a dividing line

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watershed Scientific  

/ wô′tər-shĕd′ /

1. A continuous ridge of high ground forming a divide between two different drainage basins or river systems.

2. The region enclosed by such a divide and draining into a river, river system, or other body of water.

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watershed Cultural  

1. A ridge of high land dividing two areas that are drained by different river systems. On one side of a watershed, rivers and streams flow in one direction; on the other side they flow in another direction. Also, the area drained by a water system.

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Discover More

By extension, a “watershed” is a critical point that serves as a dividing line: “The parties reached a watershed in the contract negotiations.”

Other Word Forms

Noun Inflected Forms

• watersheds
  plural

Etymology

Origin of watershed

First recorded in 1795–1805; water + shed ²

Explanation

A watershed is a turning point, or historic moment. The day you got your braces off might have been a watershed moment in your life. Watershed is a geographical term, originally. The area that drains into a single river is the watershed for that river. Watershed can also mean a ridge, like that formed by a chain of mountains, which sends water to two different rivers on either side. It's from this meaning that watershed came to mean a turning point or dividing line in social life.

Example Sentences

See Examples For:

watershed watersheds

The company added it was "exploring opportunities" for solar energy and battery storage on site, and it would make use of "non-potable, brackish groundwater" which it said would avoid putting pressure on the watershed.

From Barron's ● Aug. 7, 2026

This year, the upper portion of the river’s watershed in the Rocky Mountains had the least snow on record.

From Los Angeles Times ● Jul. 21, 2026

This watershed boxed set features cutting-edge remasters of the singer’s 1920s recordings, substantiating her centrality in blues and beyond.

From The Wall Street Journal ● Jul. 20, 2026

In a five-star reivew, Metro's Tori Brazier said, external The Oddyssey was "a watershed moment for filmmaking".

From BBC ● Jul. 15, 2026

And so it was that the weekend that was to have been a watershed in Dedd’s life turned into a trip down memory lane in a rented boat.

From "In the Time of the Butterflies" by Julia Alvarez

When exploring the watersheds east of Cuzco, Peru, he writes, Miller was “overawed by the tropical forest canopy stretching to infinity before him.”

From The Wall Street Journal ● Apr. 17, 2026

Large watersheds are far more common on Earth than on Mars.

From Science Daily ● Dec. 31, 2025

Of these, 16 formed interconnected watersheds covering at least 100,000 square kilometers.

From Science Daily ● Dec. 31, 2025

An October report published by the department indicates there have been at least 16 cloud-seeding projects across multiple counties and watersheds in California in recent years.

From Los Angeles Times ● Jul. 21, 2025

Such places, the watersheds of the great coniferous forests of spruce and balsam, of hemlock and pine, provide the kind of spawning grounds that salmon must have in order to survive.

From "Silent Spring" by Rachel Carson

Related Words

• bowl
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