amino acid


Definition of amino acid 

: an amphoteric organic acid containing the amino group NH2 especially : any of the various amino acids having the amino group in the alpha position that are the chief components of proteins and are synthesized by living cells or are obtained as essential components of the diet

Examples of amino acid in a Sentence

Recent Examples on the Web

What’s more, watermelon has an amino acid called l-citrulline, which may diminish muscle soreness after intense exercise. NBC News, "8 summer superfoods to eat after a tough workout," 11 July 2018 Plants, like all living things, need nitrogen to build amino acids and other essential biomolecules. Diana Gitig, Ars Technica, "Plants repeatedly got rid of their ability to obtain their own nitrogen," 27 May 2018 Get our daily newsletter Dr Wang knew from the botanical literature that most plants secrete from their roots a mixture of carbohydrates, amino acids and fatty acids that are food for microbes. The Economist, "A cheap way to save rice plants from the effects of acid rain," 12 July 2018 Wasps drawn to artificial sweeteners, such as those found in sodas, might be interested in the carbohydrates and amino acids in those substances. Anna Diamond, Smithsonian, "Do Marine Mammals Yawn and More Questions From Our Readers," 28 June 2018 Biotin helps with the metabolism of fatty acids, glucose (blood sugar, in other words), and amino acids in your body, the NIH reports. Korin Miller, Allure, "The Truth About Biotin Supplements, According to Nutritionists," 18 May 2018 So far, Totsch has tried Mojo Hydration's athletic recovery cocktail three times — a mix of vitamin B complex, amino acids, calcium and glutathione, an antioxidant found in plants. Zahria Rogers, The Courier-Journal, "Concierge IV hydration therapy service seeks to rehydrate Louisville," 12 July 2018 Scientists believe that the savory taste sensation results when some of our taste receptors respond to foods that contain the amino acid glutamate. Chris Ross,, "Blender gazpacho has umami flavors," 9 July 2018 Proteins are like necklaces, strung together from multiples of 20 types of amino acids. Charles S. Cockell, WSJ, "The Limits of Extra-Terrestrial Freakiness," 7 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'amino acid.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of amino acid

1897, in the meaning defined above

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amino acid


amino alcohol


Statistics for amino acid

Last Updated

16 Sep 2018

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Time Traveler for amino acid

The first known use of amino acid was in 1897

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More Definitions for amino acid

amino acid


English Language Learners Definition of amino acid

biology : any one of many acids that occur naturally in living things and that include some which form proteins

amino acid

ami·no acid | \ ə-ˈmē-nō- \

Kids Definition of amino acid

: any of various acids containing carbon and nitrogen that are building blocks of protein and are made by living plant or animal cells or are obtained from the diet

amino acid


Medical Definition of amino acid 

: an amphoteric organic acid containing the amino group NH2 especially : alpha-amino acid

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Spanish Central: Translation of amino acid

Nglish: Translation of amino acid for Spanish Speakers Encyclopedia article about amino acid

Comments on amino acid

What made you want to look up amino acid? Please tell us where you read or heard it (including the quote, if possible).


to deposit or conceal in a hiding place

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