A drainage basin, also known as a watershed or catchment area, is the geographic area that contributes water to a particular stream, river, or lake. It is defined by topographic divides, where all precipitation within the basin eventually drains into a common outlet. Drainage basins are critical in hydrology, water resource management, and environmental studies, as they influence water flow, sediment transport, and ecosystem health.
Reference: Chorley, R. J., Schumm, S. A., & Sugden, D. E. (1984). “Geomorphology.” Methuen.