Question

difference between w catchment area drainage basin and watershed

Answer 1

a river basin or drainage basin is a portion of land drained by a river and its tributaries. a river basin sends all the water falling in the surrounding land into the river. for e.g. mahanadi river basin, ganga basin.
a watershed is simply the area of land that catches rain and snow and drains or seeps into a marsh, stream river, lake or groundwater.

both river basins and watersheds are areas of land that drain to a particular water body. In the river basin, all the water drains to a large river. The term watershed is used to describe a smaller area of land that drains to a smaller stream, lake or wetland. there are many smaller watersheds within a river basin.