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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Meanwhile, other guests had reported high carbon monoxide levels and symptoms consistent with exposure, the news outlet reported. Louis Casiano, FOXNews.com, 3 Feb. 2026 Terry Miles, a 59-year-old construction worker whose home has had no electricity since a previous storm struck Sunday, resorted to using a fish fryer for heat and worried about the danger of carbon monoxide. Kristin M. Hall, Chicago Tribune, 31 Jan. 2026 Some deaths have been attributed to hypothermia; others are suspected to be related to carbon monoxide exposure. Kristin M. Hall, Los Angeles Times, 31 Jan. 2026 Deadly carbon monoxide could build up in your home. Brandee Gruener, Southern Living, 29 Jan. 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 5 Feb. 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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