arachidonic acid
noun
ar·a·chi·don·ic acid
ˌa-rə-kə-ˈdä-nik- 
ˌer-ə-
: a liquid unsaturated fatty acid C20H32O2 that occurs in most animal fats, is a precursor of prostaglandins, and is considered essential in animal nutrition
Examples of arachidonic acid in a Sentence
Recent Examples on the Web
Likewise, an omega-6 fatty acid known as arachidonic acid and vitamin E may help promote hair growth.4
7.
—
Michelle Pugle, Verywell Health, 21 Aug. 2025
Bobbie Baby Organic Powder Infant Formula also has arachidonic acid (ARA), which is another fatty acid that, together with DHA, supports infant growth and development.
—Lainey Younkin, Ms, Rd, Parents, 15 Mar. 2024
But too many of these fatty acids can cause inflammation when the body ultimately breaks them down into arachidonic acid, which lowers the body’s pain threshold.
—Sandee Lamotte, CNN, 12 Oct. 2022
According to PetMD, cats also need higher proportions of protein in their diet than dogs, as well as taurine, arachidonic acid, vitamin A and niacin.
—Jacob Livesay, USA TODAY, 22 July 2022
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Michelle Pugle, Verywell Health, 21 Aug. 2025
Bobbie Baby Organic Powder Infant Formula also has arachidonic acid (ARA), which is another fatty acid that, together with DHA, supports infant growth and development.
—Lainey Younkin, Ms, Rd, Parents, 15 Mar. 2024
But too many of these fatty acids can cause inflammation when the body ultimately breaks them down into arachidonic acid, which lowers the body’s pain threshold.
—Sandee Lamotte, CNN, 12 Oct. 2022
According to PetMD, cats also need higher proportions of protein in their diet than dogs, as well as taurine, arachidonic acid, vitamin A and niacin.
—Jacob Livesay, USA TODAY, 22 July 2022
Cite this Entry
“Arachidonic acid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/arachidonic%20acid. Accessed 3 Nov. 2025.
Copy CitationMedical Definition
arachidonic acid
noun
ar·a·chi·don·ic acid
ˌar-ə-kə-ˌdän-ik-
: a liquid unsaturated fatty acid C20H32O2 that occurs in most animal fats, is a precursor of prostaglandins and leukotrienes, and is considered essential in animal nutrition
In a biological system for the regulation of various cell functions, arachidonic acid plays a unique role as a precursor molecule which is transformed into potent mediators with far-ranging effects.—Bengt Samuelsson, Science
Bengt Samuelsson, ScienceThe prostaglandins and the leukotrienes share a common origin. They are derived, by two different enzymatic pathways, from arachidonic acid, which is formed in cells whose cell membrane has been disrupted.—Paul D. Buisseret, Scientific American
Paul D. Buisseret, Scientific AmericanFish and other vertebrates also rely on arachidonic acid, another fat, to make compounds for managing stress and immunity.—Janet Raloff, Science News
Janet Raloff, Science NewsPulmonary hypertension is thought to be due to activation and release of vasoactive mediators, including arachidonic acid metabolites, accompanied by diffuse pulmonary microvascular thrombosis—Harriet Kitzman et al., The Journal of the American Medical Association
—abbreviation AA, ARA
Harriet Kitzman et al., The Journal of the American Medical AssociationLove words? Need even more definitions?
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