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.
This ground-level ozone can form when carbon monoxide gas emitted by wildfires chemically reacts with nitrogen oxides in the presence of sunlight. — Jeanna Bryner, Scientific American, 8 June 2026 The plant also was found to have failed to conduct portable analyzer tests, which are required to determine emissions of nitrogen oxides from combustion equipment. — Tony Saavedra, Oc Register, 23 May 2026 While fine particulate matter is made of charred bits flung directly into the atmosphere by wildfires, ozone forms after the fact, when nitrogen oxides and volatile organic compounds interact with light. — Joanna Thompson, Space.com, 12 May 2026 The theory is that larger engines operating at lower stress can make more output without relying on diesel particulate filters to capture as much soot or diesel exhaust fluid to remove as much nitrogen oxide. — Caleb Jacobs, The Drive, 22 Apr. 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 8 Jul. 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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