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 cleanser also includes amino acids, ensuring your skin stays happy and healthy with each use. Poppy Morgan, Rolling Stone, 26 Sep. 2023 Here are some examples: Creatine Creatine is an amino acid that occurs naturally in food and has steroid-like effects. Amber Smith, Discover Magazine, 20 Sep. 2023 This compact moisturizer contains a gorgeous blend of niacinamide, amino acids, and squalane, which hydrates and smooths. Madison Yauger, Peoplemag, 12 Sep. 2023 Formulated with rice, keratin amino acids and enzymes (and without sulfates), the brand claims this shampoo has multiple benefits including enhancing curl retention. Catharine Malzahn, Good Housekeeping, 24 Aug. 2023 Creatine peptides promote the release of hormones that influence one's exercise performance, muscle recovery and body composition, which is why some athletes are drawn to the amino acids. Daryl Austin, USA TODAY, 22 Aug. 2023 Research suggests the drug may help rewire the brain by affecting its production of the amino acid glutamate, which acts as a neurotransmitter. Emily Maloney, STAT, 7 Sep. 2023 Sutherland and his group had previously shown that analogs of right-handed transfer RNA molecules — which bind amino acids and bring them to the ribosome to make proteins — link to left-handed amino acids 10 times faster than to right-handed ones. Yasemin Saplakoglu, Quanta Magazine, 6 Sep. 2023 The main ingredient in this dog food is rabbit meal, which provides essential proteins and amino acids necessary for your dog's overall health and well-being. Amber Smith, Discover Magazine, 17 Aug. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'amino acid.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1897, in the meaning defined above

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

Dictionary Entries Near amino acid

Cite this Entry

“Amino acid.” Dictionary, Merriam-Webster, Accessed 3 Oct. 2023.

Kids Definition

amino acid

ami·​no acid
: 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

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

More from Merriam-Webster on amino acid

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