amino acid

noun

: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Sugar beet reacts with the amino acids in the top layer of the skin to create a natural glow. Jenny Berg, Vogue, 2 June 2025 Apparently, the fat and a specific amino acid in the nut butter act as a nice complement to the onion. Karla Walsh, Better Homes & Gardens, 31 May 2025 Fake tan lotions typically contain an ingredient called dihydroxyacetone (DHA), a color additive that darkens the skin by reacting with amino acids in the skin's surface. Lucy Notarantonio, MSNBC Newsweek, 30 May 2025 That’s all thanks to the Maillard reaction, which occurs when sugars interact with the amino acids of proteins to create new, delicious flavors and aroma compounds, and also heightens the umami. The Washington Post, San Diego Union-Tribune, 28 May 2025 See All Example Sentences for amino acid

Word History

First Known Use

1897, in the meaning defined above

Time Traveler
The first known use of amino acid was in 1897

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Cite this Entry

“Amino acid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/amino%20acid. Accessed 10 Jun. 2025.

Kids Definition

amino acid

noun
ami·​no acid
ə-ˈmē-nō-
: any of numerous acids that include some which are the building blocks of proteins and are made by living cells from simpler compounds or are obtained in the diet

Medical Definition

amino acid

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

More from Merriam-Webster on amino acid

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