nitrogen dioxide


: 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 The blue flames also emit harmful pollutants like nitrogen dioxides, as well as planet-warming gases. Hiroko Tabuchi, New York Times, 30 May 2023 The key question is whether nitrogen dioxide exposure related to gas stoves is large enough to lead to health concerns. The Conversation, Ars Technica, 4 Nov. 2023 The Air Quality Index measures five major pollutants: ground-level ozone, particle pollution (which includes small particulate matter, or PM2.5, that is of particular concern with wildfire smoke), carbon monoxide, sulfur dioxide and nitrogen dioxide. NBC News, 8 June 2023 Previous studies have concluded that gas stoves produce nitrogen dioxide, a lung irritant linked to asthma and a precursor to smog. Tony Briscoe, Los Angeles Times, 21 June 2023 There were greater associations between depression and exposure to particle pollution and nitrogen dioxide among socioeconomically disadvantaged groups. Jen Christensen, CNN, 10 Feb. 2023 Any flame unites nitrogen and oxygen in the air to produce nitrogen dioxide, an irritant that triggers asthma attacks in those who are susceptible and does so without the nasal congestion that warns people of an impending asthma attack when they’re exposed to allergens such as perfume. Michael Segal, WSJ, 2 Feb. 2023 This image shows nitrogen dioxide over New York City, Philadelphia and Washington D.C., just after 12 p.m. ET on Aug. 2, 2023. Emily Mae Czachor, CBS News, 28 Aug. 2023 Pockets of nitrogen dioxide pollution are visible over cities and transit routes. Will Sullivan, Smithsonian Magazine, 5 Sep. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'nitrogen dioxide.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

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.” Dictionary, Merriam-Webster, Accessed 24 Feb. 2024.

Kids Definition

nitrogen dioxide

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

Medical Definition

nitrogen dioxide

: a poisonous strongly oxidizing reddish brown gas NO2

More from Merriam-Webster on nitrogen dioxide

Last Updated: - Updated example sentences
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