noun, often attributive
\ ˈō-shən How to pronounce ocean (audio) \

Definition of ocean

1a : the whole body of salt water that covers nearly three fourths of the surface of the earth
b : any of the large bodies of water (such as the Atlantic Ocean) into which the great ocean is divided
2 : a very large or unlimited space or quantity

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Examples of ocean in a Sentence

We've sailed across hundreds of miles of ocean. the Pacific and Indian oceans
Recent Examples on the Web Scientists predict that plastic in the ocean will outweigh fish by 2050. BostonGlobe.com, "A diver probing the deepest part of the ocean in search of exotic marine life last spring found an unexpectedly familiar sight – a plastic shopping bag and candy wrappers outside the submarine’s window, more than 35,000 feet below the ocean surface in the Marianas Trench.," 22 Nov. 2019 Now reports Lauren Oiye said yes just before Chris Garth dropped the ring in the ocean. USA TODAY, "Surfboard proposal, Duke dorm opossum, Sky Bar’s back: News from around our 50 states," 15 Nov. 2019 But the best telltale is that the tourists are the only ones swimming in the ocean. Paul Cappiello, The Courier-Journal, "A look inside how some plants are able to tolerate the cold Kentucky winters," 15 Nov. 2019 This method is best suited for dolphins living in the open ocean while those in different environments have developed unique techniques. Claire Bugos, Smithsonian, "Watch Dolphins Punt, Thrash and Trap Their Prey," 14 Nov. 2019 Scientists’ understanding of the physical processes in the ocean is slowly deepening. Richard Hodson, Scientific American, "Physical oceanography," 13 Nov. 2019 This finding, described in a paper published Tuesday in the journal eLife, is the latest in a series of studies showing the transmissible cancers are more common than previously believed—especially in the ocean. Douglas Main, National Geographic, "Rare cancers spreading among sea creatures have scientists perplexed," 8 Nov. 2019 The numbers of sawfish in the ocean have declined dramatically over the years, according to the National Oceanic and Atmospheric Administration. Harmeet Kaur, CNN, "A man could get a year in prison and a $50,000 fine for killing an endangered sawfish," 4 Nov. 2019 Etzioni posits such a computer could calculate solutions to climate change, the over-saturation of plastic in oceans, and potential asteroid strikes. NBC News, "'Terminator' at 35: How AI and the militarization of tech has evolved," 2 Nov. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ocean.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of ocean

14th century, in the meaning defined at sense 1a

History and Etymology for ocean

Middle English occean "the sea flowing around the land mass of the known world," borrowed from Anglo-French, borrowed from Latin Ōceanus, borrowed from Greek Ōkeanós, probably of pre-Greek substratal origin

Note: Preserved variants of Greek Ōkeanós, as Ōgḗn, Ōgenós, Ōgēnós, may indicate that the velar stop, whatever its original voicing, was palatalized (hence *ūkʸān-?)—strongly suggesting non-Indo-European origin. Old attempts to find an Indo-European origin (as a comparison with Sanskrit ā-śayāna- "lying on") are unconvincing.

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Time Traveler for ocean

Time Traveler

The first known use of ocean was in the 14th century

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Statistics for ocean

Last Updated

25 Nov 2019

Cite this Entry

“Ocean.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/ocean. Accessed 7 December 2019.

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More Definitions for ocean


How to pronounce ocean (audio)

English Language Learners Definition of ocean

: the salt water that covers much of the Earth's surface
: one of the five large areas of salt water that cover much of the Earth's surface
informal : a very large number or amount of something


\ ˈō-shən How to pronounce ocean (audio) \

Kids Definition of ocean

1 : the whole body of salt water that covers nearly three fourths of the earth
2 : one of the large bodies of water into which the larger body that covers the earth is divided

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More from Merriam-Webster on ocean

Thesaurus: All synonyms and antonyms for ocean

Rhyming Dictionary: Words that rhyme with ocean

Spanish Central: Translation of ocean

Nglish: Translation of ocean for Spanish Speakers

Britannica English: Translation of ocean for Arabic Speakers

Britannica.com: Encyclopedia article about ocean

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