ocean

UK: /ˈəʊʃ^ən/ US: /ˈoʊʃən/ ,(ō′shən)

WordReference Random House Learner's Dictionary of American English © 2025

o•cean /ˈoʊʃən/   n. 

1. Oceanography [uncountable* the + ~] the vast body of salt water that covers almost three-fourths of the earth's surface.
2. Oceanography [countable] any of the divisions of this body, commonly known as the Atlantic, the Pacific, the Indian, the Arctic, and the Antarctic oceans.
3. a vast quantity:
   [countable] oceans of tears.

WordReference Random House Unabridged Dictionary of American English © 2025

o•cean  (ō′shən), n. 

1. Oceanography the vast body of salt water that covers almost three fourths of the earth's surface.
2. Oceanography any of the geographical divisions of this body, commonly given as the Atlantic, Pacific, Indian, Arctic, and Antarctic oceans.
3. a vast expanse or quantity:
   an ocean of grass.

• Greek ōkeanós, Ōkeanós
• Latin ōceanus, special use of Ōceanus Oceanus
• Old French)
• Middle English ocean(e) (1250–1300

o′cean•like′, adj. 

Collins Concise English Dictionary © HarperCollins Publishers::

ocean / ˈəʊʃən/ noun

1. a very large stretch of sea, esp one of the five oceans of the world, the Atlantic, Pacific, Indian, Arctic, and Antarctic
2. the body of salt water covering approximately 70 per cent of the earth's surface
3. a huge quantity or expanse: an ocean of replies
4. the sea

Etymology: 13th Century: via Old French from Latin ōceanus, from Greek ōkeanos Oceanus