'Watershed' definitions:

Definition of 'watershed'

(from WordNet)
noun
A ridge of land that separates two adjacent river systems [syn: watershed, water parting, divide]
noun
The entire geographical area drained by a river and its tributaries; an area characterized by all runoff being conveyed to the same outlet; "flood control in the Missouri basin" [syn: river basin, basin, watershed, drainage basin, catchment area, catchment basin, drainage area]
noun
An event marking a unique or important historical change of course or one on which important developments depend; "the agreement was a watershed in the history of both nations" [syn: landmark, turning point, watershed]

Definition of 'Watershed'

From: GCIDE
  • Watershed \Wa"ter*shed`\, n. [Cf. G. wasserscheide; wasser water + scheide a place where two things separate, fr. scheiden to separate.] [1913 Webster]
  • 1. The whole region or extent of country which contributes to the supply of a river or lake. [1913 Webster]
  • 2. The line of division between two adjacent rivers or lakes with respect to the flow of water by natural channels into them; the natural boundary of a basin; -- called also divide and water parting. [1913 Webster +PJC]
  • 3. a point in time marking an important transition between two situations, or phases of an activity; a turning point. [PJC]

Definition of 'watershed'

From: GCIDE
  • Divide \Di*vide"\, n. A dividing ridge of land between the tributaries of two streams; also called watershed and water parting. A divide on either side of which the waters drain into two different oceans is called a continental divide. [1913 Webster +PJC]