fatty acid

noun

1

: any of numerous saturated aliphatic monocarboxylic acids C_nH_2n+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

Nuts Nuts like almonds, cashews, walnuts, and pistachios are rich in fiber and omega-3 fatty acids. —Carrie Madormo, Verywell Health, 16 Dec. 2025

In addition to protein, salmon also provides heart-healthy omega-3 fatty acids, and other essential nutrients like vitamin D, vitamin B12, and selenium. —Jillian Kubala, Health, 12 Dec. 2025

Most brain supplements contain omega-3-fatty acids and a variety of vitamins in various combinations, plus some fancy sounding exotic additives. —Bryant Stamford, Louisville Courier Journal, 11 Dec. 2025

This wash is rich in niacinamide (which can rev up ceramide production for a stronger moisture barrier) and shea butter, which is packed with fatty acids that work together with the lipids in your skin to help your barrier function properly. —Ian Michael Crumm, Allure, 11 Dec. 2025

Word History

First Known Use

1838, in the meaning defined at sense 1

Rhymes for fatty acid

• antacid
• placid

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 C_nH_2n+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