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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Doing so could cause a generator to produce hazardous levels of carbon monoxide, an odorless, colorless and deadly gas. Nick Lentz, CBS News, 7 Mar. 2026 The room did not have a carbon monoxide detector. Bay Area News Group, Mercury News, 6 Mar. 2026 Those guardrails are in place because air pollutants that come from the generators, like nitrogen oxides, carbon monoxide, and ‘fine particulate matter’ are known to cause lung and heart health issues when inhaled. Ashley Miznazi, Miami Herald, 5 Mar. 2026 Responders found two people passed out due to what appeared to be carbon monoxide exposure, Boston radio station WBUR reported. ABC News, 5 Mar. 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 12 Mar. 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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