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

In the second twin, some of her cells will have a four base pair deletion, which will cause a short tail of 10 random amino acids. John Timmer, Ars Technica, "Scientists, ethicists slam decisions behind gene-edited twins," 30 Nov. 2018 Usually the nurses administer a version of the Myers Cocktail, a mix of B and C vitamins, potassium, magnesium, calcium, and amino acids delivered with an intravenous needle. Jamie Rosen, Town & Country, "Is the Wellness IV the Next Big Thing in Beauty?," 15 Aug. 2018 Cockroach milk also contains protein and amino acids, which could potentially be valuable to human health. Amanda Macmillan,, "Is Cockroach Milk Really a New Superfood? Here's What We Know," 29 May 2018 Thanks to its hero ingredient shea, L’Occitane’s rich formula is soothing and replenishing for extremely dry skin, while Sk-II’s Facial Treatment Cleansing Oil’s cocktail of vitamins, amino acids, and minerals is ideal for dullness and fine lines. Lauren Valenti, Vogue, "This Missing Step in Your Beauty Routine Is the Answer to Glowing Skin," 10 Dec. 2018 In the course of about four hours, the strong alkaline base breaks down everything but the skeleton into the original components that built it: sugar, salts, peptides, and amino acids. Hayley Campbell, WIRED, "A New Way to Dispose of Corpses—With Chemistry!," 27 Mar. 2018 Rodrigues’s team combined tried-and-true barcoding with collagen fingerprinting, a technique that matches amino acids in samples’ connective tissue to known animal families. Michael Price, Science | AAAS, "Ancient seafarers may have hunted whales around the world," 10 July 2018 Choose a cream with amino acids, which trigger collagen production. Melissa Matthews, Woman's Day, "The Foolproof Anti-Aging Skin Routine," 24 Aug. 2015 This amino acid triggers the release of serotonin, which is a feel-good brain chemical. Marie Claire, "9 Foods That Reduce Stress Levels," 21 Mar. 2010

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

18 Feb 2019

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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

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to express emotion in a dramatic way

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