nitrous oxide

noun

: a colorless gas N2O that when inhaled produces loss of sensibility to pain preceded by exhilaration and sometimes laughter, that is used especially as an anesthetic in dentistry and as a fuel, and that is an atmospheric pollutant and greenhouse gas produced by combustion

called also laughing gas

compare nitric oxide

Examples of nitrous oxide in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The long history of nitrous oxide as a recreational drug Recreational use of nitrous oxide dates back more than two centuries. Ella Jeffries, Smithsonian Magazine, 8 Apr. 2025 Months later, Bryar’s autopsy raised a possible contributing factor in his death — three canisters of nitrous oxide found next to his corpse, with tubing for inhalation still attached. August Brown, Los Angeles Times, 25 Mar. 2025 Specifically, the agency in 2009 found that six greenhouse gases in the earth's atmosphere — carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons and sulfur hexafluoride — posed a health risk to current and future generations. Kate Gibson, CBS News, 12 Mar. 2025 When the musician was found dead in his home in November 2024, he was discovered next to three large canisters of nitrous oxide, according to an autopsy report obtained by TMZ. Ilana Kaplan, People.com, 3 Mar. 2025 See All Example Sentences for nitrous oxide

Word History

First Known Use

1798, in the meaning defined above

Time Traveler
The first known use of nitrous oxide was in 1798

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Cite this Entry

“Nitrous oxide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/nitrous%20oxide. Accessed 22 Apr. 2025.

Kids Definition

nitrous oxide

noun
: a colorless gas that when inhaled causes loss of the ability to feel pain and sometimes produces laughter and is used especially in dentistry

called also laughing gas

Medical Definition

nitrous oxide

noun
: a colorless gas N2O that when inhaled produces loss of sensibility to pain preceded by exhilaration and sometimes laughter and is used especially as an anesthetic in dentistry

called also laughing gas

More from Merriam-Webster on nitrous oxide

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