A circular or oval valley, or depression of the surface of the ground, the lowest part of which is generally occupied by a lake, or traversed by a river.
The entire tract of country drained by a river, or sloping towards a sea or lake.
An isolated or circumscribed formation, particularly where the strata dip inward, on all sides, toward a center; -- especially applied to the coal formations, called coal basins or coal fields.
A natural depression on the earth's surfaces, in which (usually water-borne) sediments accumulate over millions of years. The Gulf of Mexico is an example.
A hollow vessel or dish, to hold water for washing, and for various other uses.
A hollow place containing water, as a pond, a dock for ships, a little bay.
A shallow sink.
Either an oceanic region with coherent features (e.g. the north Indian Ocean Basin), or a set of bathymetric data for use in numerical models.
See ocean basin.
A large, cup-shaped dent in the ocean floor.