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

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Expenditures on non-vitamin brain health supplements such as such as minerals, herbal mixtures, nurtraceuticals or amino acids, have extended into the billions of dollars. Steven Dekosky, The Conversation, "Supplements for brain health show no benefit – a neurologist explains a new study," 20 June 2019 As such, it’s said to be chock full of vitamins, amino acids, minerals, and organic acids, all of which provide a myriad of skin-brightening, smoothing, and plumping benefits. Allure, "What You Need to Know About The “Skip Care” Skin-Care Trend," 14 June 2019 In sweet, domesticated varieties, a mutation in the bHLH2 protein—caused by swapped amino acids, the components that make up proteins—prevents it from binding to these genes, stopping them from making amygdalin. Jennifer Leman, Scientific American, "The Bitter Truth: Scientists Sequence the Almond Genome," 13 June 2019 Proteins are large, complicated molecules made up of hundreds or thousands of smaller units called amino acids, which are attached to each other in long chains and fold up into different shapes. Martin Finucane,, "What if you could play a video game that helps find a cure for cancer?," 7 June 2019 Photo: Justin Zoll Crystals of amino acids, magnified four times in an image taken by Justin Zoll, are the building blocks of proteins. Daniela Hernandez, WSJ, "From Tears to Spider Embryos: Photos Reveal World’s Microscopic Wonders," 12 Oct. 2018 It's made with honey extract, which nurtures skin, and royal jelly (a honey bee secretion)—both deliver all the good things (amino acids, vitamins, and minerals) to your face. Maya Mcdowell, Seventeen, "These Superfood-Inspired Beauty Products Are a *Must* for Your Most Annoying Skin Issues," 21 May 2019 The famous double helix of a DNA strand twists right, along with the sugars that comprise its backbone; the amino acids in proteins twist left. Luba Ostashevsky, Ars Technica, "How did life begin? It’s Chemistry 101, but in space," 26 Feb. 2018 Broth: Soups and stews (which provide immune-boosting amino acids and minerals) can feel soothing, while the heat helps open up congestion. Good Housekeeping, "Exactly What to Eat to Boost Your Immune System, According to a Registered Dietitian," 30 Jan. 2019

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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Dictionary Entries near amino acid




amino acid


amino alcohol


Statistics for amino acid

Last Updated

24 Jun 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

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 take the place or position of

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