The mesopelagic (Greek μέσον, middle) (also known as the middle pelagic or twilight zone) is a pelagic zone extending from 200 m (650 ft.) down to around 1000 m (3280 ...

Any water in the sea that is not close to the bottom or near to the shore is in the pelagic zone. The word pelagic comes from the Greek πέλαγος ...

The benthic zone is the ecological region at the lowest level of a body of water such as an ocean or a lake, including the sediment surface and some sub-surface ...

An ocean (from Greek Ὠκεανὸς, "okeanos" OceanusὨκεανός, Henry George Liddell, Robert Scott, A Greek-English Lexicon, at Perseus project) is a major body of saline water, and a principal component ...