noun, often attributive
ox·​y·​gen | \ ˈäk-si-jən \

Definition of oxygen 

1 : a reactive element that is found in water, in most rocks and minerals, in numerous organic compounds, and as a colorless tasteless odorless diatomic gas constituting 21 percent of the atmosphere, that is capable of combining with all elements except the inert gases, that is active in physiological processes, and that is involved especially in combustion — see Chemical Elements Table
2 : something that sustains or fuels disagreement is the true oxygen of these magazines— Joseph Epstein

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Other Words from oxygen

oxygenless \ ˈäk-​si-​jən-​ləs \ adjective

Examples of oxygen in a Sentence

Recent Examples on the Web

Multiple teams using the same device have experienced similar oxygen system failures. Alan Arnette, Outside Online, "Everest Summit Bids Cut Short by Equipment Failure," 16 May 2018 And many species that have an enormous value to ocean ecosystems, such as crucial oxygen-generating bacteria, do not have easily quantifiable benefits to humanity, so are difficult to insure. Emma Farge, The Christian Science Monitor, "Natural ocean barriers could soon be covered by insurance," 15 May 2018 Media: Melissa Phillip, Houston Chronicle The hulking, 11-foot-tall spacecraft looming in the middle of a warehouse at NASA's Johnson Space Center lacks seats, oxygen systems and parachutes. Alex Stuckey, Houston Chronicle, "NASA's Johnson Space Center preps Orion module for test of emergency systems," 25 Apr. 2018 That in turn prevents the human body from becoming oxygen-starved after minutes below water, researchers said. Jared Gilmour, miamiherald, "Human 'sea nomads' can dive up to 13 minutes — thanks to this DNA mutation, study finds | Miami Herald," 19 Apr. 2018 Officials had alleged maintenance contractor SabreTech improperly prepared, labeled and packaged the oxygen-generating canisters believed to have caused the crash. Lisa J. Huriash, Sun-Sentinel.com, "Fugitive mechanic in deadly 1996 ValuJet crash 'never should have been charged,' lawyer says," 14 Apr. 2018 Max was born with tetralogy of Fallot, a congenital heart condition that causes oxygen-poor blood to leave the heart and flow through the rest of the body. Jason Duaine Hahn, PEOPLE.com, "Mini-Darth Vader Made Famous in Iconic Super Bowl Ad to Have His 13th Heart Surgery," 2 Feb. 2018 Wheeling her oxygen tank behind her, Aguirre came dressed to vote in an orange beanie and a BETO FOR SENATE T-shirt, determined to elect the El Paso representative over incumbent (and Republican) Senator Ted Cruz. Abby Gardner, Glamour, "Watch This 77-Year-Old Texas Woman Get Emotional Over Voting for Senate Candidate Beto O'Rourke," 6 Nov. 2018 Other efforts to promote their story have included construction of a museum and the anointing as a national hero of a former Thai navy SEAL who died while diving in the cave delivering oxygen tanks. Fox News, "Thai cave story moves to Bangkok mall with boys taking stage," 6 Sep. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'oxygen.' 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 oxygen

1788, in the meaning defined at sense 1

History and Etymology for oxygen

French oxygène, from Greek oxys, adjective, acidic, literally, sharp + French -gène -gen; akin to Latin acer sharp — more at edge

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Statistics for oxygen

Last Updated

15 Jan 2019

Look-up Popularity

Time Traveler for oxygen

The first known use of oxygen was in 1788

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More Definitions for oxygen



English Language Learners Definition of oxygen

: a chemical that is found in the air, that has no color, taste, or smell, and that is necessary for life


ox·​y·​gen | \ ˈäk-si-jən \

Kids Definition of oxygen

: a chemical element found in the air as a colorless odorless tasteless gas that is necessary for life


ox·​y·​gen | \ ˈäk-si-jən \

Medical Definition of oxygen 

: a colorless tasteless odorless gaseous element that constitutes 21 percent of the atmosphere and is found in water, in most rocks and minerals, and in numerous organic compounds, that is capable of combining with all elements except the inert gases, that is active in physiological processes, and that is involved especially in combustion processes symbol O — see Chemical Elements Table

Other Words from oxygen

oxygenic \ ˌäk-​si-​ˈjen-​ik \ adjective

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More from Merriam-Webster on oxygen

Spanish Central: Translation of oxygen

Nglish: Translation of oxygen for Spanish Speakers

Britannica English: Translation of oxygen for Arabic Speakers

Britannica.com: Encyclopedia article about oxygen

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