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 This compound also releases amino acids that are essential for protein and collagen synthesis. Adele Jackson-gibson, Good Housekeeping, "Is Sea Moss Healthy? Here's How to Eat It for Maximum Benefits," 17 Jan. 2020 Our bodies need nine amino acids—the building blocks of protein—to make muscle. National Geographic, "These traditional diets can lead to long lives," 17 Dec. 2019 Because the sequences of amino acids in proteins vary slightly from person to person based on their genetic code, this information can be used to identify people with a high degree of accuracy without DNA. Eva Frederick, Science | AAAS, "Scientists can now identify someone from a single strand of hair," 21 Nov. 2019 The Maillard reaction occurs when the amino acids in high-protein foods such as cheese and pepperoni react with the sugars in those foods when heated. Jeffrey Miller, Washington Post, "The combinations and the cooking process enhance the taste of already-tasty ingredients.," 4 Nov. 2019 Sold in mass retailers such as Walgreens and Walmart, Closys instead uses stabilized chlorine dioxide, which is naturally activated by the amino acids in saliva, to impede plaque formation and kill harmful bacteria. Claire Ballentine,, "The $100 Tube of Toothpaste Is Here," 24 Sep. 2019 His findings helped scientists engineer varieties of corn with higher levels of the amino acids lysine and methionine, essential building blocks of proteins that people can get only from their diet. New York Times, "Joachim Messing, 73, Who Charted the DNA of Viruses and Plants, Dies," 27 Sep. 2019 The Bader formula is based on TFC8 (Trigger Factor Complex 8), a proprietary cocktail of over 40 different ingredients, including vitamins and amino acids. Sarah Wu, Glamour, "Augustinus Bader's $265 'Miracle Cream' Rarely Goes on Sale—Except Today," 29 Nov. 2019 Fear of the dark is an arrangement of fifteen amino acids. Hilton Als, The New Yorker, "Joan Didion’s Early Novels of American Womanhood," 25 Nov. 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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Time Traveler for amino acid

Time Traveler

The first known use of amino acid was in 1897

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Statistics for amino acid

Last Updated

21 Jan 2020

Cite this Entry

“Amino acid.” The Dictionary, Merriam-Webster Inc., Accessed 24 January 2020.

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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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a feeling of well-being or elation

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