Abstract: Watershed is a commonly used concept in hydrology, geomorphology, etc. But the disorder use of this term is a common problem in many disciplines. Based on sketching related terms of watershed and its connotations, we try to solve the problems of applicability and essence of watershed, and suggest the concept of watershed discriminated as three different sub-concepts, that is, special definition, general definition and geo-morphological definition.

Key words: drainage basin, catchment area, watershed, drainage divide