fatty acid

American  

noun

Biochemistry.

1. any of a class of aliphatic acids, especially palmitic, stearic, or oleic acid, consisting of a long hydrocarbon chain ending in a carboxyl group that bonds to glycerol to form a fat.

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fatty acid British  

noun

1. any of a class of aliphatic carboxylic acids, such as palmitic acid, stearic acid, and oleic acid, that form part of a lipid molecule

2. another name for carboxylic acid, used esp of a naturally occurring one

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fatty acid Scientific  

/ făt′ē /

1. Any of a large group of organic acids, especially those found in animal and vegetable fats and oils. Fatty acids are mainly composed of long chains of hydrocarbons ending in a carboxyl group. A fatty acid is saturated when the bonds between carbon atoms are all single bonds. It is unsaturated when any of these bonds is a double bond.

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Etymology

Origin of fatty acid

First recorded in 1860–65

Example Sentences

"Our work really confirms the fact that DHA alone cannot do the work, but we have this other fatty acid that is seemingly working and improving vision in aged animals," she says.

From Science Daily • Apr. 22, 2026

In those animals, the absence of ALOX15 led to a rise in colorectal tumors, although the impact varied depending on which omega-3 fatty acid was used.

From Science Daily • Feb. 13, 2026

In this study, Lovaza as well as the ethyl ester and free fatty acid forms of EPA reduced both the number and size of tumors, particularly in mice that had active ALOX15.

From Science Daily • Feb. 13, 2026

Headquartered in the central Chinese city of Wuhan, Cabio Biotech is one of the world's largest producers of ARA, a fatty acid used primarily in baby formula and food products.

From Barron's • Jan. 31, 2026

Omega-6 is another fatty acid essential to humans.

From "The Omnivore's Dilemma" by Michael Pollan