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 The source of the conflict is nitrogen pollution, which comes in two forms: nitric oxides (NOx), mainly from combustion engines, and ammonia, mostly from fertiliser and animal waste. The Economist, "A tiny environmental group wins a huge victory," 26 Oct. 2019 Molecular studies have suggested that pretomanid has a complex killing method, potentially busting the bacteria’s cell walls while also poisoning the germs by the release of nitric oxide. Beth Mole, Ars Technica, "How a new antibiotic destroys extremely drug-resistant tuberculosis," 16 Aug. 2019 Excess free hemoglobin will therefore rob the blood of nitric oxide, constrict blood vessels and potentially cause hypertension and reduced blood flow to the organs. Quanta Magazine, "Icefish Study Adds Another Color to the Story of Blood," 22 Apr. 2019 The detectors can provide breakdowns of how much carbon dioxide, carbon monoxide, nitric oxide, nitrogen dioxide, ozone and particulate matter are in the environment. Travis Fedschun, Fox News, "Google Street View cars to be outfitted with pollution sensors to measure US, Europe air quality," 18 Sep. 2018 Here’s what else this veggie can do: Help your heart: The glycolipids in spinach promote the body’s production of nitric oxide (NO), which helps dilate blood vessels and reduce atherosclerosis. Jaclyn London, Ms, Rd, Cdn, Good Housekeeping, "Spinach Is the Legit Superfood You Need in Your Life," 22 Mar. 2018 Red Beets Beets are high in nitrates, which our bodies use to make nitric oxide, which in turn signals blood vessels to relax, helping widen the arteries and increase circulation, bringing more oxygen to hardworking muscles. Sara Angle, Outside Online, "Athletes, Stock Up on This Powerhouse Summer Produce," 22 June 2018 The body converts that nitrate to nitrite and then to nitric oxide, which seems to make your muscles work more efficiently during endurance exercise. Alex Hutchinson, Outside Online, "Sunlight May Be the Next Beet Juice," 22 Mar. 2018 The paper also contains a line that the vampire Master didn't considered: Big nuke blasts will block sunlight but the temperature extremes also cause a lot of nitric oxides to enter the atmosphere. Joe Pappalardo, Popular Mechanics, "Hollywood Has No Idea How Nukes Work," 2 Apr. 2018

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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Last Updated

19 Nov 2019

Time Traveler for nitric oxide

The first known use of nitric oxide was in 1789

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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)

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