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.
Patchen studies how omega-3 fatty acids and vitamin D — another nutrient that fish is rich in — are associated with better lung function and lower risk of chronic obstructive pulmonary disease and emphysema. — Diana Anos, CNN Money, 4 Sep. 2026 Key Takeaways Omega-3 fatty acids, found in fish and seeds, may help with ADHD symptoms. — Heather Jones, Verywell Health, 31 Aug. 2026 This looks like prioritizing foods that are high in calcium, vitamin D, and omega-3 fatty acids. — Sarah Madaus, InStyle, 30 Aug. 2026 Fatty Fish Fatty fish like salmon and sardines are among the richest sources of omega-3 fatty acids, particularly DHA. — Lynn Andriani, Martha Stewart, 30 Aug. 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 6 Sep. 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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