niacin

noun

ni·​a·​cin ˈnī-ə-sən How to pronounce niacin (audio)
: an acid C6H5NO2 of the vitamin B complex found widely in animals and plants and used especially against pellagra
also : nicotinamide

called also nicotinic acid

Examples of niacin in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Most varieties also contain B vitamins such as thiamin, niacin and folate. — Daryl Austin, USA Today, 3 May 2026 In addition to protein, peanuts provide heart-healthy unsaturated fats, magnesium, niacin, and folate. — Lindsey Desoto, Health, 3 June 2026 In many cases, the culprit is a hidden stimulant, although high-dose B vitamins and niacin can also contribute to symptoms in some cases. — Sara Hoffman, Verywell Health, 29 June 2026 Dark chocolate also contains some vitamins, including vitamins K, B12, thiamin, riboflavin, niacin, and pantothenic acid. — Mura Dominko, Martha Stewart, 11 Feb. 2026 See All Example Sentences for niacin

Word History

Etymology

nicotinic acid + -in entry 1

First Known Use

1942, in the meaning defined above

Time Traveler
The first known use of niacin was in 1942

Rhymes for niacin

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Browse Nearby Words

Ni
niacin
niacinamide
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Cite this Entry

“Niacin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/niacin. Accessed 7 Jul. 2026.

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Kids Definition

niacin

noun
ni·​a·​cin ˈnī-ə-sən How to pronounce niacin (audio)
: an acid of the vitamin B complex that is found widely in plants and animals and is used especially against pellagra

called also nicotinic acid

Medical Definition

niacin

noun
ni·​a·​cin ˈnī-ə-sən How to pronounce niacin (audio)
: a crystalline acid C6H5NO2 that is a member of the vitamin B complex occurring usually in the form of a complex of niacinamide in various animal and plant parts (as blood, liver, yeast, bran, and legumes) and is used especially to lower LDL and triglyceride levels in the blood and to treat pellagra

called also nicotinic acid

More from Merriam-Webster on niacin

Nglish: Translation of niacin for Spanish Speakers

Britannica.com: Encyclopedia article about niacin

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