monoxide

American  

[mon-ok-sahyd, muh-nok-] / mɒnˈɒk saɪd, məˈnɒk- /

noun

Chemistry.

1. an oxide containing one oxygen atom in each molecule.

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monoxide British  

/ mɒˈnɒksaɪd /

noun

1. an oxide that contains one oxygen atom per molecule

   carbon monoxide, CO

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monoxide Scientific  

/ mə-nŏk′sīd′ /

1. A compound consisting of two elements, one of which is a single oxygen atom. Carbon monoxide, for example, contains a carbon atom bound to a single oxygen atom.

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Etymology

Origin of monoxide

First recorded in 1865–70; mon- + oxide

Example Sentences

He defended crafts chain Michael’s against claims that toxic levels of carbon monoxide at one of its stores caused brain damage to an employee’s unborn daughter.

From The Wall Street Journal • Apr. 7, 2026

A rom-com need not be a sparkling shelf covered with bon-bons, but it shouldn’t be a nauseating cloud of carbon monoxide that makes you want to flee.

From The Wall Street Journal • Apr. 2, 2026

Burning them releases carbon monoxide, nitrogen oxides and fine particles that penetrate the lungs and bloodstream.

From BBC • Mar. 19, 2026

Det Chief Insp Ben Robinson said that although the post-mortem examinations, which were held on Sunday, were yet to establish a cause, carbon monoxide poisoning remained a primary line of inquiry.

From BBC • Feb. 23, 2026

“Carbon monoxide plus iron gives the volatile iron carbonyl.”

From "I, Robot" by Isaac Asimov