Dictionary.com
Thesaurus.com

amino acids

Cultural  
  1. Basic organic molecules (see also organic molecule) that combine to form proteins. Amino acids are made up of hydrogen, carbon, oxygen, and nitrogen. Some examples of amino acids are lysine, phenylalanine, and tryptophan.


Discover More

Amino acids are the basic molecular building blocks of proteins.

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Ingest a small but powerful tab of L.A.-grown protein-rich amino acids optimized to enhance their longevity and fat-burning properties, and let the aminos take you away.

From Los Angeles Times • Apr. 1, 2026

Technically speaking, peptides are short chains of amino acids that act as messengers in the body.

From The Wall Street Journal • Mar. 22, 2026

"The ammonia goes into amino acids and nucleotides, both of which tumor cells depend on for growth," said Zong.

From Science Daily • Mar. 6, 2026

Some organisms assign different amino acids to certain codons, some use more than the standard 20 amino acids, and multiple codons can correspond to the same amino acid.

From Science Daily • Feb. 28, 2026

Beans have both lysine and tryptophan, but not the amino acids cysteine and methionine, which are provided by maize.

From "1491" by Charles C. Mann