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

The Euros had been too fast—too fast to have climbed the mountain with bottled oxygen, let alone without it. The Editors, Outside Online, "The Moments That Changed Us," 11 July 2018 It is then mixed with atmospheric oxygen to generate an electric current which drives a motor. Jordan Blum, Houston Chronicle, "Exxon Mobil, Chevron help form new methane emissions consortium," 25 June 2018 With oxygen that is free of gases and air pollution, the mountain air of Beaver Creek is fresh and clean. Discover Magazine, "5 Reasons Why Golfing in the Mountains Is Ideal," 25 June 2018 Now, cleaner and enriched with oxygen, nutrients and enzymes, the blood warms and enriches skin and muscles, and range of motion increases. Lamar Dawson, GQ, "Cryotherapy Might Be the Best Way to Recover from Joint Pain," 16 June 2018 To meet all the requirements, Soviet engineers designed a lamp filled with oxygen and containing metallic foil or powder. Anatoly Zak, Popular Mechanics, "The Soviet Laser Space Pistol, Revealed," 14 June 2018 More on the Detroit Zoo: Heavy-duty fish shipping bags filled with oxygen were used to transport the tadpoles safely. Caroline Blackmon, Detroit Free Press, "Puerto Rico just got 11,000 toads courtesy of the Detroit Zoo," 12 June 2018 There have been 123 overdoses through April, and most are brought back with oxygen. New York Times, "Opioid Crisis Compels New York to Look North for Answers," 21 May 2018 Bring boxes or coolers to transport fish — the koi will be put in a new plastic bag with oxygen. Linda Mcintosh, sandiegouniontribune.com, "Boys & Girls Club member wins state title," 18 May 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

22 Oct 2018

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

Comments on oxygen

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a state of commotion or excitement

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