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

The best barrier repair creams have equal parts cholesterol, ceramides and fatty acids to mimic the skin’s natural lipid structure. —Leslie Baumann, Miami Herald, 23 Jan. 2026

Fish don't produce omega-3 fatty acids themselves, but from ingesting marine algae in their diet. —Shirl Leigh january 23, New Atlas, 23 Jan. 2026

Specifically, fatty fish are rich in EPA and DHA, which are types of omega-3 fatty acids that help lower triglycerides (another type of fat in the blood), reduce inflammation, and support healthy heart rhythm, Routhenstein says. —Beth Krietsch, SELF, 22 Jan. 2026

Keeping natural light from the seeds protects the omega fatty acids and ensures the seeds won’t be rancid upon opening. —Bestreviews, Mercury News, 22 Jan. 2026

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