noun
a ridge of land that separates two adjacent river systems
Synonyms
noun
the entire geographical area drained by a river and its tributaries
Synonyms
river basin
basin
drainage basin
catchment area
catchment basin
drainage area
Examples
- an area characterized by all runoff being conveyed to the same outlet
- flood control in the Missouri basin
noun
an event marking a unique or important historical change of course or one on which important developments depend
Synonyms
Examples
- the agreement was a watershed in the history of both nations