ocean

n. one of the large bodies of water covering the Earth (i.e. Atlantic, Pacific, Indian, Arctic, and Antarctic Oceans); large quantity; great distance

An ocean (from , Okeanos (Oceanus) in Greek) is a major body of saline water, and a principal component of the hydrosphere. Approximately 71% of the Earth's surface (an area of some 361 million square kilometers) is covered by ocean, a continuous body of water that is customarily divided into several principal oceans and smaller seas. More than half of this area is over 3,000 meters (9,800 ft) deep. Average oceanic salinity is around 35 parts per thousand (ppt) (3.5%), and nearly all seawater has a salinity in the range of 31 to 38 ppt.
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Noun
1. a large body of water constituting a principal part of the hydrosphere
(hypernym) body of water, water
(hyponym) Antarctic Ocean
(part-holonym) hydrosphere
(class) body of water, water
2. anything apparently limitless in quantity or volume
(synonym) sea
(hypernym) large indefinite quantity, large indefinite amount

n. ocean, one of the large bodies of water covering the Earth (i.e. Atlantic, Pacific, Indian, Arctic, and Antarctic Oceans)

(n.)
The whole body of salt water which covers more than three fifths of the surface of the globe; -- called also the sea, or great sea.
  

(n.)
One of the large bodies of water into which the great ocean is regarded as divided, as the Atlantic, Pacific, Indian, Arctic and Antarctic oceans.
  

(n.)
An immense expanse; any vast space or quantity without apparent limits; as, the boundless ocean of eternity; an ocean of affairs.
  

(a.)
Of or pertaining to the main or great sea; as, the ocean waves; an ocean stream.