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
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.
In California, the trucks are only 6% of vehicles on the road, but account for about 35% of harmful nitrogen oxide emissions and 25% of greenhouse gas emissions from vehicles, according to the California Air Resources Board. — Los Angeles Times, 27 Aug. 2026 Regulators say the facility is expected to emit air pollutants including nitrogen oxides, volatile organic compounds, particulate matter, various metals and other compounds associated with human cremation. — Alula Alderson, Sacbee.com, 24 Aug. 2026 Again, an idling engine still emits exhaust gases such as carbon monoxide, nitrogen oxides, and hydrocarbons, and these emissions will ultimately end up in the air and contribute to air pollution. — Molly Burford, Southern Living, 22 Aug. 2026 Also, hydrogen combustion can still produce nitrogen oxides, or NOx, because combustion heats nitrogen and oxygen from the air to very high temperatures. — Christopher McFadden, Interesting Engineering, 9 Aug. 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
See all Nearby Words

Cite this Entry

“Nitrogen oxide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/nitrogen%20oxide. Accessed 1 Sep. 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

Last Updated: - Updated example sentences
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