Wiktionary
hadal
a. of, or relating to the deepest parts of the ocean
WordNet
hadal
adj. relating to the deepest parts of the ocean (below 6000 meters)
Wikipedia
Hadal (album)
Hadal is the third album by Velcra released in 2007.
Usage examples of "hadal".
A great number have been sightings of transients and freight riders and animals, even tree branches scratching at the window, not hadals.
All five of the gracile hadals had shaped skulls, flattened on back from binding in infancy.