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

Volatile organic compounds and carbon monoxide are the key ingredients in ground-level ozone pollution, which combine on hot days to create a smog that fouls the air. —Noelle Phillips, Denver Post, 9 Apr. 2026

Flat Can Recycling will recycle household items for a fee at the event, including latex paint cans, household batteries, aerosol products, propane tanks, carbon monoxide and smoke detectors and car seats, according to organizers. —Aurora Beacon-News, Chicago Tribune, 8 Apr. 2026

The report notes that gas stoves can emit pollutants such as nitrogen dioxide, carbon monoxide and particulate matter, which may accumulate indoors if ventilation is inadequate. —Liz O'Connell, MSNBC Newsweek, 31 Mar. 2026

The carbon isotopes are found on 3I/ATLAS in compounds such as carbon monoxide and carbon dioxide, and even organic molecules such as methanol, formaldehyde and methane. —Keith Cooper, Space.com, 30 Mar. 2026

Word History

First Known Use

1868, in the meaning defined above

Rhymes for carbon monoxide

• hydroxide
• tetroxide

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