Noun: drainage basin 'drey-nij'bey-sun
- 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 drainage basin";
- river basin, basin, watershed, catchment area, catchment basin, drainage area
Derived forms: drainage basins
Type of: geographic area, geographic region, geographical area, geographical region
Encyclopedia: Drainage basin