Definition of watershed in English:

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Pronunciation: /ˈwôdərˌSHed/


1An area or ridge of land that separates waters flowing to different rivers, basins, or seas.
Example sentences
  • In the Marin watershed on Pumpkin Ridge, Davidson showed me a site where Rizzo and other scientists had injected some healthy coast live oaks with P. ramorum.
  • O'Grady and Geslin were still in the lead, some hundred miles into the stage, when the peloton climbed steadily into the area known as Le Forez, the watershed between the rivers Saone and Rhone.
  • These included aggregations sampled along parallel watersheds in the Madawaska Highlands for examining fine geographic scale population structure.
1.1An area or region drained by a river, river system, or other body of water.
Example sentences
  • The Penobscot River drains the largest watershed in Maine and is the U.S. Fish and Wildlife Service's flagship river for the restoration of Atlantic salmon in the country.
  • These sources are particularly important because the rivers drain watersheds that don't receive much summer rainfall and where rates of evaporation are relatively high.
  • Opponents of the project worry the resulting salty waste water will find its way into the local watershed and into river systems leading south into Montana.
2An event or period marking a turning point in a course of action or state of affairs: these works mark a watershed in the history of music
More example sentences
  • This essay starts from the observation that the 1993 general election marked a major watershed in Canadian party politics.
  • Publication of this story marks a watershed in American political history.
  • The Kosovo War was a watershed event that profoundly changed the political situation.
turning point, milestone, landmark


Early 19th century: from water + shed in the sense 'ridge of high ground' (related to shed2), suggested by German Wasserscheide, literally 'water-divide'.

For editors and proofreaders

Syllabification: wa·ter·shed

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