carbon monoxide

noun

: a colorless odorless very toxic gas CO that is formed as a product of the incomplete combustion of carbon or a carbon compound

Examples of carbon monoxide 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.
First Alert Plug-in Carbon Monoxide Detector For solo travelers, a carbon monoxide detector can be a smart addition to your hotel or vacation rental safety kit. — Nneya Richards, Travel + Leisure, 11 Oct. 2026 In Florida’s Escambia County, Sheriff Chip Simmons said a woman was killed when a tree fell on her home and a man died of carbon monoxide fumes from a generator running in his garage. — Emilie Megnien, Los Angeles Times, 10 Oct. 2026 After turning the oven and two burners on for 15 minutes, those figures rose to 89 ppm for carbon monoxide and 180 ppb for nitrogen dioxide. — Carol J. Williams, Chicago Tribune, 1 Oct. 2026 Ozone, which is made up of three oxygen atoms, forms when emissions of other pollutants such as carbon monoxide and nitrogen oxides from fossil-fuel burning or wildfires mix with sunlight and heat. — Mary Randolph, Scientific American, 30 Sep. 2026 See All Example Sentences for carbon monoxide

Word History

First Known Use

1868, in the meaning defined above

Time Traveler
The first known use of carbon monoxide was in 1868

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Cite this Entry

“Carbon monoxide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/carbon%20monoxide. Accessed 15 Oct. 2026.

Kids Definition

carbon monoxide

noun
: a colorless odorless very poisonous gas formed by the incomplete burning of carbon

Medical Definition

carbon monoxide

noun
: a colorless odorless very toxic gas CO that burns to carbon dioxide with a blue flame and is formed as a product of the incomplete combustion of carbon

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