nitric oxide


Definition of nitric oxide

: a colorless poisonous gas NO formed by oxidation of nitrogen or ammonia that is present in the atmosphere and also in mammals where it is synthesized from arginine and oxygen and acts as a vasodilator and as a mediator of cell-to-cell communication (as between nerve cells) — compare nitrous oxide

Examples of nitric oxide in a Sentence

Recent Examples on the Web McKeown explains that nitric oxide is produced in the sinuses and is known to be antibacterial, anti-fungal, anti-pathogenic and antiviral. Daryl Austin, USA TODAY, 21 Sep. 2021 Loss of nitric oxide is recognized as one of the earliest events in the onset and progression of every major chronic disease. Annie Brown, Forbes, 25 Oct. 2021 What's more, the overwhelming inflammation that can occur with severe Covid-19 causes the body to produce nitric oxide, and that, in turn, dilates blood vessels, leading to dangerously low blood pressure in some patients. NBC News, 10 Sep. 2021 Outside of EmitBio’s research, there have been several studies exploring the potential of nitric oxide to treat Covid patients. Alex Knapp, Forbes, 1 Sep. 2021 Research is limited on the benefits of nitric oxide in physical performance, but one piece of evidence suggests supplements with L-citrulline and other vasodilators can increase the amount of nutrients transported to muscle groups. Zee Krstic, Good Housekeeping, 29 Aug. 2021 In addition to helping prevent forward-head posture, inhaling through your nose expresses nitric oxide, a natural vasodilator that increases oxygenation. Dana Santas, CNN, 23 June 2021 The devices convert harmful exhaust gases such as carbon monoxide and nitric oxide into carbon dioxide and water vapor. Jacob Beltran, San Antonio Express-News, 11 June 2021 This compound helps increase nitric oxide production, which relaxes the lining of your blood vessels and enables them to widen. Serena Coady, Glamour, 4 June 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'nitric oxide.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of nitric oxide

1789, in the meaning defined above

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Time Traveler for nitric oxide

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The first known use of nitric oxide was in 1789

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Dictionary Entries Near nitric oxide

nitric anhydride

nitric oxide


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Statistics for nitric oxide

Last Updated

24 Dec 2021

Cite this Entry

“Nitric oxide.” Dictionary, Merriam-Webster, Accessed 27 Jan. 2022.

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nitric oxide


Medical Definition of nitric oxide

: a poisonous colorless gas NO that occurs as a common air pollutant formed by the oxidation of atmospheric nitrogen and that is also formed by the oxidation of arginine in the mammalian body where it acts as a mediator of intracellular and intercellular communication regulating numerous biological processes (as vasodilation and neurotransmission)

More from Merriam-Webster on nitric oxide Encyclopedia article about nitric oxide


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