ar·a·chi·don·ic acid 
(ăr′ə-kĭ-dŏnĭk)
(ăr′ə-kĭ-dŏnĭk)n.
An unsaturated fatty acid, C20H32O2, present in animal fats and synthesized by the body from linoleic acid, that is essential in human nutrition and is a precursor in the biosynthesis of some prostaglandins.
[From arachidic, of the groundnut, from New Latin Arachis, groundnut genus, from Greek arakis, arakid-, diminutive of arakos, a leguminous plant.]
- radiometric
- radiometric dating
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- radiomimetic
- radionuclide
- radiopacity
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- radiopharmaceutical
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- radioscopic
- radioscopical
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