pelagic

Etymology

From Latin pelagicus (and possibly pelagus); from Ancient Greek πελαγικός (pelagikós), from πέλαγος (pélagos, “sea”).

adj

1. (biology) Living in the open sea rather than in coastal or inland waters.
   Besides, seeing a shark in an aquarium tank is not the same as seeing a shark in the wild, in its natural, pelagic habitat. 1983, Richard Ellis, The Book of Sharks, Knopf, page 13
2. Of or pertaining to oceans.
   Drifting idly around a broad oceanic arc, the bottle collides softly with tens of thousands of pelagic plastics all colonized by hard-shelled organisms, including barnacles, coralline algae, foraminifera and bivalve molluscs. 2020, David Farrier, “The Bottle as Hero”, in Footprints, 4th Estate

noun

1. (biology) Any organism that lives in the open sea rather than in coastal or inland waters.