basin [basins](area of land that drains into a common outlet) noun [UK: ˈbeɪs.n̩] [US: ˈbeɪs.n̩]
drainage basin [drainage basins](topographic region in which all water drains to a common outlet) noun [UK: ˈdreɪ.nɪdʒ ˈbeɪs.n̩] [US: ˈdreɪ.nədʒ ˈbeɪs.n̩]