benthic
adjective·/ˈbɛn.θɪk/
Of the bottom of a sea, lake, or river. Dwelling on, in, or near the substrate. Benthic life is shaped by pressure, darkness, and the slow economies of sediment.
The diver hovered above the benthic plain, watching starfish move with a patience the surface world never learns.
Etymology
From Greek benthos "the depths (of the sea)." The scientific adjective maps a vertical world, oriented not by north and south but by surface and floor.
Related Words
pelagicof the open water, away from the bottom
abyssalof the deepest ocean zones
littoralof the shore region
demersalliving near the bottom; often used of fish