watershed

[waw-ter-shed, wot-er-]

noun

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.

adjective

1. constituting a watershed.

   a watershed area; a watershed case.

watershed

/ 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

watershed

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.

watershed

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.

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

Word History and Origins

Origin of watershed¹

First recorded in 1795–1805; water + shed ²

Example Sentences

Myers’s case turned out to be a watershed event for aircrew in the U.S., recognized as the first time a court has ruled that fume exposure caused a plaintiff’s long-term health conditions.

Read more on Wall Street Journal

"It was a watershed in my life because it made me realise there was a world outside Byres Road," he once said, referring to the street at the heart of the city's West End.

Read more on BBC

"This was a systemic failure that demands real accountability and must serve as a watershed moment to end the cruel practice of keeping elephants and other social animals isolated in our zoos for good."

Read more on BBC

For the Beatles and the world, “Rubber Soul” marked a watershed moment — an unmistakable harbinger for innovative and even more provocative works of musical art.

Read more on Salon

Computer animation’s watershed moment for feature films happened just 30 years ago with the debut of Pixar’s “Toy Story.”

Read more on Los Angeles Times

Related Words

• bowl 
• lagoon 
• pan 
• pool 
• pot 
• tub 
• valley