fatty acid

noun

1
: any of numerous saturated aliphatic monocarboxylic acids CnH2n+1COOH (such as acetic acid) including many that occur naturally usually in the form of esters in fats, waxes, and essential oils
2
: any of the saturated or unsaturated monocarboxylic acids (such as palmitic acid) usually with an even number of carbon atoms that occur naturally in the form of glycerides in fats and fatty oils

Examples of fatty acid 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.
Ceramides support the skin barrier, while squalane and fatty acids help lock in moisture for a smoother, glowier-looking neck. — Christa Joanna Lee, Glamour, 23 Oct. 2026 Hemp seeds contain protein, fiber, lipids, amino acids, vitamins A, D, and E, and omega-6 and omega-3 fatty acids. — Amber J. Tresca, Verywell Health, 22 Oct. 2026 At the top of the ranking are foods rich in unsaturated fatty acids, including extra-virgin olive oil, nuts, seeds, olives, avocados, and fatty fish. — Laura Solla, Vogue, 21 Oct. 2026 Aside from vitamin B12, organ meats like kidneys are nutrient-dense, providing substantial amounts of essential amino acids, iron, selenium, zinc, copper, phosphorus, and omega-3 fatty acids. — Joy Emeh, HEALTH, 19 Oct. 2026 See All Example Sentences for fatty acid

Word History

First Known Use

1838, in the meaning defined at sense 1

Time Traveler
The first known use of fatty acid was in 1838

Rhymes for fatty acid

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Browse Nearby Words

fatty
fatty acid
fatty liver
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Cite this Entry

“Fatty acid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fatty%20acid. Accessed 27 Oct. 2026.

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Kids Definition

fatty acid

noun
: any of numerous acids that contain only carbon, hydrogen, and oxygen and occur naturally in fats and various oils

Medical Definition

fatty acid

noun
1
: any of numerous saturated aliphatic acids CnH2n+1COOH (as lauric acid) containing a single carboxyl group and including many that occur naturally usually in the form of esters in fats, waxes, and essential oils
2
: any of the saturated or unsaturated organic acids (as palmitic acid) that have a single carboxyl group and usually an even number of carbon atoms and that occur naturally in the form of glycerides in fats and fatty oils

More from Merriam-Webster on fatty acid

Britannica.com: Encyclopedia article about fatty acid

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