watershed

Definition

The topographical boundary dividing two adjacent catchment basins, such as a ridge or a crest.

Etymology

From water + shed. A calque of German Wasserscheide.

Example Sentences

• "After Lesjaverk (23 miles) the eastern end of Lesjaskogsvatn is reached. This lake has the distinction of being a watershed. From the east end flows the Lågen, the great river that runs down Gudbrandsdal to Lake Mjøsa, while from the west end the Rauma River emerges to flow down to the Romsdalfjord."
• "In the minds of many, 1847 was a watershed year during which Ceres, Pallas, Juno, Vesta, and Astraea were reclassified as asteroids."
• "Coronavirus has been a watershed for the railways. It has accelerated the decline of season tickets and reduced business travel after years of steadily rising passenger numbers."