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.
Hydrogen evolution is therefore suppressed, leaving more opportunity for CO₂-derived pathways that produce carbon monoxide and formate. — Rupendra Brahambhatt, Interesting Engineering, 10 Aug. 2026 This is a tiny amount, millions of times lower than the atmospheric pressure on Earth, resulting from Pluto's thin nitrogen atmosphere that also contains hazes made from organic molecules including methane and carbon monoxide. — Keith Cooper, Space.com, 10 Aug. 2026 Cove sent me a full array of add-ons, including indoor and outdoor cameras, a doorbell camera, a smoke detector, a carbon monoxide (CO) detector, a panic button, a glass-break sensor, a water-leak sensor, a siren, and a remote fob. — John R. Delaney, PC Magazine, 10 Aug. 2026 Now, authorities are investigating if a generator was running inside the house, resulting in possible carbon monoxide poisoning, WRAL reported. — Sam Gillette, PEOPLE, 5 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 14 Aug. 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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