say it: WAW-tur-shed
watershed is a noun meaning "a ridge of land that separates two adjacent river systems". It carries 3 recorded senses.
a ridge of land that separates two adjacent river systems
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”
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”
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for watershed come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.