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

Studies in animal models have also shown that oleic acid, a fatty acid found in olive oil, can enhance the function of the intestinal barrier by increasing the levels of beneficial bacteria in the gut, specifically Bifidobacteria. —Angelica Bottaro, Verywell Health, 22 Oct. 2025

High in Omega-3 Fatty Acids Salmon is one of the best sources of omega-3 fatty acids (omega-3s). —Merve Ceylan, Health, 22 Oct. 2025

University of Utah researchers found that triple-negative breast cancer (TNBC)—an aggressive type of invasive breast cancer—is fueled by lipids and that these fatty acids are a key feature of obesity that promote tumor growth. —Hannah Millington, MSNBC Newsweek, 16 Oct. 2025

This bacteria ferments fiber into short-chain fatty acids that enhance Treg cell function and help maintain gut health. —Mitzi Nagarkatti, The Conversation, 10 Oct. 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