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A sulfur-containing essential amino acid, C5H11NO2S, obtained from various proteins or prepared synthetically and used as a dietary supplement and in pharmaceuticals.
(Elements & Compounds) an essential amino acid containing sulphur, which occurs in many proteins: important in methylating reactions
[C20: meth- + thionine]
me•thi•o•nine(mɛˈθaɪ əˌnin, -nɪn)
an essential amino acid, C5H11NO2S, occurring in casein, yeast, and other proteins. Abbr.: Met; Symbol: M
An essential amino acid. See more at amino acid.