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.
Police said the preliminary findings show carbon monoxide levels in the vehicle were at levels exceeding what is considered safe. — Michael Guise, CBS News, 30 June 2026 In February 2025, three women died of carbon monoxide poisoning at a hotel in Belize. — Olivia Young, Travel + Leisure, 17 June 2026 Fire officials also encourage having working smoke and carbon monoxide detectors on every level of the home, including smoke detectors in every bedroom. — Justin Muszynski, Hartford Courant, 10 June 2026 As an example, regulations requiring carbon monoxide detectors allowed people to prevent or escape dangerous carbon monoxide buildup in their homes. — David C. Schwebel, The Conversation, 24 June 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 7 Jul. 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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