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

Example Sentences

Recent Examples on the Web Promescent's VitaFLUX for Women is an all-natural L-arginine nitric oxide booster that improves blood flow and hormone production in women. Amber Smith, Discover Magazine, 21 Dec. 2022 That’s because a particular group of ingredients in pre-workouts can increase nitric oxide. Dallas News, 25 Jan. 2022 First, VigRX Plus includes a few ingredients that can increase your nitric oxide levels. Dallas News, 23 Dec. 2022 It's crafted with LJ100 Longjack along with nitric oxide and other ingredients like ginkgo extract and Asian ginseng. Amber Smith, Discover Magazine, 20 Oct. 2022 This combination includes unique amino acids that help to generate nitric oxide, which the body uses to manage blood flow. Amber Smith, Discover Magazine, 21 Dec. 2022 Expect more energy, nitric oxide (pumps), reduced soreness and fatigue from taking just one scoop. Dallas News, 25 Jan. 2022 Second, the company’s data suggests the light frequency triggers the product of nitric oxide, which the body’s immune system uses for a number of different purposes, including fighting infectious disease. Alex Knapp, Forbes, 1 Sep. 2021 Panax ginseng extract may also work on nitric oxide production, which boosts blood flow in rats. Dallas News, 12 Jan. 2023 See More

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Word History

First Known Use

1789, in the meaning defined above

Time Traveler
The first known use of nitric oxide was in 1789

Dictionary Entries Near nitric oxide

Cite this Entry

“Nitric oxide.” Dictionary, Merriam-Webster, Accessed 28 May. 2023.

Medical Definition

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

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