wa·​ter·​shed ˈwȯ-tər-ˌshed How to pronounce watershed (audio)
plural watersheds
: a dividing ridge between drainage areas : divide entry 2
The watershed of the Himalayas does not lie along the line of its highest peaks, as in most mountain ranges, but about a hundred miles farther north.Frits Staal
: a region or area bounded peripherally by a divide and draining ultimately to a particular watercourse or body of water
the Mississippi River watershed
: a crucial dividing point, line, or factor : turning point
This year marked a watershed for contemporary classical music in the city.The Chicago Tribune
The spring of 1949 was, in general, a watershed in Joe Liebling's life.Raymond Sokolov
The death of Ugandan teacher Gregory Byaruhanga at the hands of the Kenyan police has marked a watershed in the rising tension in the region and in the instability of the Kenyan regime.Victoria Brittain
often used before another noun
a watershed moment
a watershed event
The watershed year for science fiction must be 1968, when Stanley Kubrick's 2001: A Space Odyssey appeared, not only dramatically expanding for this kind of motion picture the potentials of film technology, but making science fiction a vehicle for both poetic vision and metaphysical exploration.Ira Konigsberg
British : the time of day after which television programs not appropriate for children may be broadcast
the nine o'clock watershed
medical : an area of tissue (as of the brain or colon) that is located at the periphery of two separate arterial systems, is dependent on both for blood supply, and may be poorly perfused and vulnerable to ischemia
usually used before another noun
Brain imaging of patients with vascular dementia typically show small strokes or poor blood supply deep in the brain, at the natural terminal (the so-called watershed area) of the blood vessel.Renee Meyer
… cell death caused by blocked blood flow in the brain's "watershed" region, where two arteries supply blood.Susan Scutti
see also watershed infarction

Did you know?

Watershed Has Geographic Origins

Opinion on the literal geographic meaning of watershed is divided. On one side of the debate are those who think the word can only refer to a ridge of land separating rivers and streams flowing in one direction from those flowing in the opposite direction. That's the term's original meaning, one probably borrowed in the translation of the German Wasserscheide. On the other side of the argument are those who think watershed can also apply to the area through which such divided water flows. The latter sense is now far more common in America, but most Americans have apparently decided to leave the quarrel to geologists and geographers while they use the term in its figurative sense, "turning point."        

Examples of watershed in a Sentence

The show will not air until after the nine o'clock watershed. a watershed moment in her life came when she inherited a reasonable sum of money and was able to start her own coffee shop
Recent Examples on the Web Madeline Heim is a Report for America corps reporter who writes about environmental issues in the Mississippi River watershed and across Wisconsin. Madeline Heim, Journal Sentinel, 5 July 2024 The Yavapai-Apache Nation will also waive, among other things, claims for damages to water rights against existing water users in the Verde River watershed and against the United States. Debra Utacia Krol, The Arizona Republic, 2 July 2024 Candy wrappers, chip bags and other refuse regularly wind up in the watershed, as do pesticides and herbicides from lawns and horticulture programs. Hayley Smith, Los Angeles Times, 30 June 2024 The wolves traveled in watersheds in Routt, Jackson, Larimer, Grand, Eagle and Summit counties between May 21 and June 25, the map shows. Elise Schmelzer, The Denver Post, 26 June 2024 See all Example Sentences for watershed 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'watershed.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1764, in the meaning defined at sense 1a

Time Traveler
The first known use of watershed was in 1764


Dictionary Entries Near watershed

Cite this Entry

“Watershed.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/watershed. Accessed 17 Jul. 2024.

Kids Definition


wa·​ter·​shed ˈwȯt-ər-ˌshed How to pronounce watershed (audio)
: a dividing ridge (as a mountain range) separating one drainage area from others
: the area that drains into a river or lake

More from Merriam-Webster on watershed

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