[1] : The Collaborative International Dictionary of English v.0.48

watershed \wa"tershed`\, 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
see also:
divide water parting 

[2] : The Collaborative International Dictionary of English v.0.48

divide \divide"\, 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
see also:
watershed water parting continental divide 

[3] : WordNet (r) 2.0

watershed
     n 1: a ridge of land that separates two adjacent river systems
          syn: water parting, divide
     2: 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
see also:
water parting divide landmark turning point 

Watershed >> W Words
Watershed, definition of term: Watershed
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