watershed meaning and definition

WATERSHED noun

Definition of watershed (noun)

1. a ridge of land that separates two adjacent river systems
   • synonyms: divide, water parting
2. 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"
   • synonyms: basin, catchment area, catchment basin, drainage area, drainage basin, river basin
3. 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"
   • synonyms: landmark, turning point