nitrogen dioxide

noun

: a toxic reddish brown gas NO2 that is a strong oxidizing agent, is produced by combustion (as of fossil fuels), and is an atmospheric pollutant (as in smog)

Examples of nitrogen dioxide in a Sentence

Recent Examples on the Web
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On top of spewing nitrogen dioxide, a gas that causes irreversible respiratory damage over time, the turbines emit a horrendous sound that’s made life miserable for locals. Joe Wilkins, Futurism, 16 Apr. 2026 The report notes that gas stoves can emit pollutants such as nitrogen dioxide, carbon monoxide and particulate matter, which may accumulate indoors if ventilation is inadequate. Liz O'Connell, MSNBC Newsweek, 31 Mar. 2026 Pollution from both nitrogen dioxide and fine particles dropped between 2012 and 2022, while carbon emissions from vehicles went down by 35%, according to a study by Airparif. Marie Patino, Bloomberg, 20 Mar. 2026 London maintains an emissions limit of 40 micrograms per cubic meter of nitrogen dioxide. Jasmin Malik Chua, Sourcing Journal, 5 Feb. 2026 See All Example Sentences for nitrogen dioxide

Word History

First Known Use

1869, in the meaning defined above

Time Traveler
The first known use of nitrogen dioxide was in 1869

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Cite this Entry

“Nitrogen dioxide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/nitrogen%20dioxide. Accessed 21 Apr. 2026.

Kids Definition

nitrogen dioxide

noun
: a reddish brown poisonous gas that is an air pollutant formed from automobile exhausts

Medical Definition

nitrogen dioxide

noun
: a poisonous strongly oxidizing reddish brown gas NO2

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