noun, often attributive
ox·​y·​gen | \ ˈäk-si-jən How to pronounce oxygen (audio) \

Definition of oxygen

1 : a chemical element that constitutes 21 percent of the Earth's atmosphere, that is capable of combining with all elements except some noble gases, that is active in physiological processes of almost all known organisms, 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

Other Words from oxygen

oxygenless \ ˈäk-​si-​jən-​ləs How to pronounce oxygen (audio) \ adjective

Examples of oxygen in a Sentence

Recent Examples on the Web To his political life, the U.S. Constitution is his oxygen and not necessarily convincing people to vote for him in the next election. Paul Gattis | Pgattis@al.com, al, 10 May 2022 The only byproduct is oxygen in contrast to carbon monoxide from other methods. Ian Palmer, Forbes, 1 May 2022 Although both girls have breathing tubes to help with their oxygen, the twins are thriving and still like to be close to each other, according to TODAY. Asha C. Gilbert, USA TODAY, 22 Jan. 2022 Fowler’s testimony blamed Floyd’s death on heart disease and drug use rather than his oxygen being cut off while pinned beneath Chauvin’s knee for more than nine minutes. Washington Post, 2 Jan. 2022 Chemical elements such as phosphorus, which can deprive rivers of their oxygen, were ignored. Rick Noack, Anchorage Daily News, 29 Dec. 2021 When my fever broke, my oxygen went to 69, and I was rushed to the hospital. Brianne Tracy, PEOPLE.com, 22 Dec. 2021 Haley has learned that there is simply no oxygen in the current iteration of the Republican Party for criticism of Trump. Chris Cillizza, CNN, 6 Oct. 2021 Water will serve as the primary source of IPP’s hydrogen, splitting molecules into oxygen and hydrogen gases through electrolysis. Leia Larsen, The Salt Lake Tribune, 1 May 2022 See More

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.

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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oxygen-acetylene cutting

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Statistics for oxygen

Last Updated

21 May 2022

Cite this Entry

“Oxygen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/oxygen. Accessed 24 May. 2022.

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More Definitions for oxygen


ox·​y·​gen | \ ˈäk-si-jən How to pronounce oxygen (audio) \

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 How to pronounce oxygen (audio) \

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 How to pronounce oxygen (audio) \ adjective

More from Merriam-Webster on 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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