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

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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.
Redensyl pairs larch wood and green tea leaf extracts with amino acids to promote a healthy follicle environment. — Christa Joanna Lee, Allure, 28 Aug. 2026 Packed with potent ingredients like isopropyl cloprostenate, amino acids, hyaluronic acid, and vitamin E, this formula nurtures and enhances your brows from the root. — Iman Balagam, Vogue, 27 Aug. 2026 It’s packed with skincare ingredients like peptides, vitamin B3, amino acids, and seaweed extract, which actively reduce fine lines and brighten your complexion during wear. — Izzy Baskette, PEOPLE, 27 Aug. 2026 Drinking Buddies is a liquid that claims to contain DHM along with an acetaldehyde-busting amino acid, herbs such as milk thistle, and B vitamins. — Shayla Love, New Yorker, 26 Aug. 2026 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

Rhymes for amino acid

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Browse Nearby Words

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amino acid
aminoaciduria
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Cite this Entry

“Amino acid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/amino%20acid. Accessed 2 Sep. 2026.

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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

Britannica.com: Encyclopedia article about amino acid

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