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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In addition to smoke and soot, the space agency detected large plumes of harmful gases emanating from the wildfires, including lung-irritating nitrogen dioxide and cancer-causing formaldehyde. Tony Briscoe, Los Angeles Times, 16 Jan. 2025 The researchers suggest that these white lights arise due to a combination of heating in the ionosphere due to the surrounding aurora, as well as the chemiluminescence of some other gases in the atmosphere, possibly nitrogen dioxide. Yaakov Katz, Newsweek, 13 Jan. 2025 The waiver can be used to rein in toxic, smog-causing pollutants like soot, nitrogen dioxide and ozone that lead to asthma and lung disease. Coral Davenport, New York Times, 14 Dec. 2024 Almost all people living in large cities breathe elevated levels of nitrogen dioxide (NO2); a pollutant linked to the development of childhood asthma as well as the aggravation of existing asthma symptoms. Laurie Winkless, Forbes, 26 Nov. 2024 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

Dictionary Entries Near nitrogen dioxide

Cite this Entry

“Nitrogen dioxide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/nitrogen%20dioxide. Accessed 15 Feb. 2025.

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

More from Merriam-Webster on nitrogen dioxide

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