plural watersheds
Definition of watershed
1a : 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
b : a region or area bounded peripherally by a divide and draining ultimately to a particular watercourse or body of water
the Mississippi River watershed
2 : 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 nouna watershed momenta watershed eventThe 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
3 British : the time of day after which television programs not appropriate for children may be broadcast
the nine o'clock watershed
4 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 nounBrain 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
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Time Traveler for watershed
The first known use of watershed was in 1764
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