natural depression

Thesaurus

Noun

1.

natural depression - a sunken or depressed geological formation depression basin - a natural depression in the surface of the land often with a lake at the bottom of it; "the basin of the Great Salt Lake" bed, bottom - a depression forming the ground under a body of water; "he searched for treasure on the ocean bed" crater - a bowl-shaped depression formed by the impact of a meteorite or bomb geological formation, formation - (geology) the geological features of the earth hollow, hole - a depression hollowed out of solid matter lowland - low level country sinkhole, swallow hole, sink - a depression in the ground communicating with a subterranean passage (especially in limestone) and formed by solution or by collapse of a cavern roof oceanic abyss, trench, deep - a long steep-sided depression in the ocean floor trough - a narrow depression (as in the earth or between ocean waves or in the ocean bed) vale, valley - a long depression in the surface of the land that usually contains a river natural elevation, elevation - a raised or elevated geological formation