HADAL
- of or pertaining to the greatest ocean depths, below approximately 20,000 ft. (6500 m)
- of or pertaining to the biogeographic region of the ocean bottom below the abyssal zone
- of, relating to, or being the parts of the ocean below 6000 meters (about 20,000 feet)
- pertaining to deep parts of the ocean [adj]
- pertaining to the ocean depths [adj]