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monoxide

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

noun

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


monoxide British  
/ mɒˈnɒksaɪd /

noun

  1. an oxide that contains one oxygen atom per molecule

    carbon monoxide, CO

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

monoxide Scientific  
/ mə-nŏksīd′ /
  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.


Etymology

Origin of monoxide

First recorded in 1865–70; mon- + oxide

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Researchers believe this change is caused by temperature effects rather than an actual increase in carbon monoxide abundance.

From Science Daily • Jun. 11, 2026

State media initially reported four deaths and dozens trapped after levels of carbon monoxide -- a highly toxic, odourless gas -- in the mine were found to have "exceeded limits".

From Barron's • May 23, 2026

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

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

From BBC • Mar. 19, 2026

It didn't look much like a factory—no towering steel silos or smokestacks billowing carbon monoxide, just a few buildings that vaguely reminded him of airplane hangars.

From "An Abundance of Katherines" by John Green

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