hadal
adjective
ha·dal ˈhā-dᵊl 
: of, relating to, or being the parts of the ocean below 6000 meters (about 20,000 feet)
Example Sentences
Recent Examples on the Web In studies, more than half of sampled hadal organisms—those living in the deepest parts of the ocean, beyond 20,000 feet—had plastics in their gut. 
Timothy Shank, Scientific American, 1 Aug. 2022 No other system could so precisely map hadal depths. Ben Taub, The New Yorker, 10 May 2020 Life at the extremes Welcome to the hadal zone: the deepest part of the ocean. Eva Botkin-kowacki, The Christian Science Monitor, 23 Aug. 2019
Timothy Shank, Scientific American, 1 Aug. 2022 No other system could so precisely map hadal depths. Ben Taub, The New Yorker, 10 May 2020 Life at the extremes Welcome to the hadal zone: the deepest part of the ocean. Eva Botkin-kowacki, The Christian Science Monitor, 23 Aug. 2019 Word History
Etymology
French, from Hadès Hades
First Known Use
1959, in the meaning defined above
- of course
- of course not
- of few words
- of help
- of hers
- of his
- of humble origin
- of humble origin(s)
- of humble origins
- of independent means
- of interest
- of its own accord
- of late
- of like mind
- of little avail
- of mature years
- of means
- of mercy
- of mine
- of moment
- of natural causes
- of necessity
- of no avail
- of note
- of old