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
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Newlight also reported a 28 percent reduction in CO₂ emissions and a 22 percent decrease in carbon monoxide emissions during the voyage. — Aamir Khollam, Interesting Engineering, 3 Sep. 2026 Other alleged violations — which total 23 in all — range from not having any smoke or carbon monoxide detectors throughout the property to failing to maintain the building in a structurally safe and stable condition. — Tess Kenny, Chicago Tribune, 1 Sep. 2026 Carrollton-Farmers Branch ISD separately said a carbon monoxide alarm was activated due to ongoing construction on campus. — Doug Myers, CBS News, 27 Aug. 2026 The medical examiner’s office previously said that foul play was not suspected, but that carbon monoxide poisoning has been ruled out as a possibility. — Justin Muszynski, Hartford Courant, 25 Aug. 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

Rhymes for carbon monoxide

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Browse Nearby Words

carbon microphone
carbon monoxide
carbonnade
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Cite this Entry

“Carbon monoxide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/carbon%20monoxide. Accessed 5 Sep. 2026.

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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

More from Merriam-Webster on carbon monoxide

Britannica.com: Encyclopedia article about carbon monoxide

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