a. Pertaining to the benthonic environment on the continental slope,
ranging in depth from 200 to 2,000 m. AGI
b. Pertaining to the bottom and overlying waters between 100 and 1,000
fathoms (600 to 6,000 ft or 183 to 1,830 m). AGI
c. Of or pertaining to the deeper parts of the ocean; deep sea.
Dictionary of Mining, Mineral, and Related Terms