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
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The answer, which the students also gleaned from slides of the case study’s sperm sample, was no, the man shouldn’t wear constrictive clothing, nor keep exercising at such high intensity and taking high doses of Omega-3 fatty acids and nitrous oxide boosters. Michelle L. Quinn, Chicago Tribune, 17 July 2025 And if that wasn't enough, there’s a literal nitrous oxide canister tucked between the two rear titanium silencers. New Atlas, 15 July 2025 Here, that mill, which already produces 140 hp and 110 ft lbs of torque, is also accompanied by a nitrous oxide bottle. Bryan Hood, Robb Report, 8 July 2025 Canisters of compressed nitrous oxide work in the same way. Kaitlin Sullivan, NBC news, 2 July 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 4 Aug. 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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