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

Their breakthrough revealed that the signal represented five amino acids—the fundamental building blocks of life. —Tom Howarth follow, Newsweek, 4 Nov. 2024

They’re loaded with a brightening and rejuvenating blend of vitamins, amino acids, minerals, and organic acids. —Audrey Lee, Architectural Digest, 1 Nov. 2024

Key Ingredients: Vitamin C, rosehip oil, collagen, amino acids, grapeseed oil Best For: Formulated for normal to dry skin types, the cream firms sagginess and brightens dark spots. —Jenny Berg, Vogue, 31 Oct. 2024

Other key ingredients to look out for include vitamins, amino acids, and natural chemicals, which work to strengthen, hydrate, and regrow your hair. —Alyssa Brascia, People.com, 29 Oct. 2024

Word History

First Known Use

1897, in the meaning defined above

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