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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.
Keep the exhaust pipe free of blockage to prevent carbon monoxide poisoning. Ryan Murphy, IndyStar, 29 Nov. 2025 Check batteries in smoke alarms and carbon monoxide detectors. Doyle Rice, USA Today, 28 Nov. 2025 This device simply plugs into the wall outlet and will display a red LED light if carbon monoxide is present. Merrell Readman, Travel + Leisure, 27 Nov. 2025 There were no carbon monoxide alarms in the home, but people living there called 911 after feeling dizzy and getting headaches, spokesperson Maria Carabajal said. Katie Langford, Denver Post, 26 Nov. 2025 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 1 Dec. 2025.

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

Last Updated: - Updated example sentences
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