Underwater
Part of speech: adjective
Definition: beneath the surface of the water, or of or pertaining to the region beneath the water surface beneath the water line of a vessel having negative equity; owing more on an asset than its market value
Part of speech: noun
Definition: underlying water or body of water, for example in an aquifer or the deep ocean A type of lure which lies beneath the water surface.
Part of speech: verb
Definition: to water or irrigate insufficiently
Example sentence: I am an underwater explorer, not a treasure hunter.
Subsurface
Part of speech: noun
Definition: Something that is below the layer that is on the surface.A surface which is a submanifold of another surface.
Part of speech: adjective
Definition: below the surface