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

Definition of oxygen

1 : a chemical element that constitues 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

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Other Words from oxygen

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

Examples of oxygen in a Sentence

Recent Examples on the Web

Simple formula: Shake the forecheck, gain some oxygen, light up the scoreboard. Kevin Paul Dupont, BostonGlobe.com, "Here’s how the Bruins turned the tables on the Blues in Game 6," 10 June 2019 Wildfires require the interaction of three elements: oxygen, fuel and ignition. San Diego Union-Tribune, "Don’t let your landscaping become a fire risk," 7 June 2019 The machine drains the body’s blood from the vein and does the work of the heart and lungs, taking out the carbon dioxide and adding the oxygen, and then returns the blood to the body. Shari Rudavsky, Indianapolis Star, "The machine that saved Millie — and 999 other Riley kids before her," 6 June 2019 And since oats also contain iron (a mineral which helps deliver oxygen to red blood cells) and magnesium (which aids nerve and muscle function), oatmeal is my go-to recommendation for endurance athletes looking to maximize their stamina. Good Housekeeping, "4 Reasons Why Oatmeal Is the Ultimate Breakfast," 15 Oct. 2018 Despite the historic air, all the technology is up-to-date, so enjoy the in-room iPads, espresso/tea machines, heated bathroom floors, and pumped-in oxygen to help ease any altitude issues. Betsy Blumenthal, Condé Nast Traveler, "The Best Hotels in the World: 2018 Readers' Choice Awards," 9 Oct. 2018 All players contribute to three common goals around the terraforming effort: increasing the planet’s surface temperatures to eight Celsius, increasing the atmospheric oxygen levels to 14 percent, and placing nine ocean tiles on the board. Keith Law, Ars Technica, "Review: Super-hot board game Terraforming Mars goes digital," 10 Nov. 2018 Vulnerabilities include being able to turn a weapon on or off, affect missile targeting, adjust oxygen levels or manipulate what controllers see on their computer screens. Lolita C. Baldor, The Seattle Times, "Report: Pentagon weapons systems vulnerable to cyber attacks," 9 Oct. 2018 Another concern is the oxygen levels inside the cave could get dangerously low. Kaitlyn Schallhorn, Fox News, "Thai soccer team rescue might need to happen sooner than expected, experts warn," 2 Oct. 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

18 Jun 2019

Look-up Popularity

Time Traveler for oxygen

The first known use of oxygen was in 1788

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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 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 oxygenic (audio) \ 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

What made you want to look up oxygen? Please tell us where you read or heard it (including the quote, if possible).


incapable of being surmounted or overcome

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