nitrogen oxide

noun

: any of several oxides of nitrogen most of which are produced in combustion and are considered to be atmospheric pollutants: such as
a
: nitric oxide
b
: nitrogen dioxide
c
: nitrous oxide

Examples of nitrogen oxide in a Sentence

Recent Examples on the Web
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It can also be equipped with an SCR (Selective Catalytic Reduction) system that reduces nitrogen oxide (NOx) emissions by up to 70 percent to meet IMO Tier III regulations. — Rachel Cormack, Robb Report, 9 Oct. 2026 Burning natural gas produces nitrogen oxides, which mix with volatile organic compounds in high heat to form ground-level ozone. — Noelle Phillips, Denver Post, 3 Oct. 2026 Ozone, which is made up of three oxygen atoms, forms when emissions of other pollutants such as carbon monoxide and nitrogen oxides from fossil-fuel burning or wildfires mix with sunlight and heat. — Mary Randolph, Scientific American, 30 Sep. 2026 The rule also translates to an extra 90 tons a year of soot particles and 4,870 additional tons a year of smog components such as nitrogen oxides and volatile organic compounds emitted into the air in coming years, experts say. — Arkansas Online, 29 Sep. 2026 See All Example Sentences for nitrogen oxide

Word History

First Known Use

1868, in the meaning defined above

Time Traveler
The first known use of nitrogen oxide was in 1868

Rhymes for nitrogen oxide

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Browse Nearby Words

nitrogenous
nitrogen oxide
nitrogen pentoxide
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Cite this Entry

“Nitrogen oxide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/nitrogen%20oxide. Accessed 14 Oct. 2026.

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Kids Definition

nitrogen oxide

noun
: any of various oxides of nitrogen: as
a
: nitrogen dioxide
b
: nitrous oxide

More from Merriam-Webster on nitrogen oxide

Britannica.com: Encyclopedia article about nitrogen oxide

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