nitric oxide

noun

: 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

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One of the molecules that causes those capillaries to open up is called nitric oxide; the discovery of its role in circulation was rewarded with a Nobel Prize, in 1998, and led to, among other things, the development of Viagra. Nicola Twilley, The New Yorker, 3 Feb. 2025 Beets are a source of nitrate, which helps form nitric oxide in the body. Merve Ceylan, Health, 29 Jan. 2025 His own research has helped show that even tiny amounts of hemoglobin outside a red cell can cause immense damage by scavenging nitric oxide. Nicola Twilley, The New Yorker, 3 Feb. 2025 This can increase nitric oxide production, improving blood flow and muscle oxygen delivery.7 Nitric oxide also regulates various functions of skeletal muscles, including muscle contraction and repair. Lindsey Desoto, Rd, Ld, Verywell Health, 29 Jan. 2025 See all Example Sentences for nitric oxide 

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.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/nitric%20oxide. Accessed 22 Feb. 2025.

Medical Definition

nitric oxide

noun
: 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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