histidine
noun
his·ti·dine
ˈhi-stə-ˌdēn 
: a crystalline essential amino acid C6H9N3O2 formed by the hydrolysis of most proteins
Examples of histidine in a Sentence
Recent Examples on the Web
Nine essential amino acids—histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine—are available only through foods or supplements.
—
Stacey Colino, Time, 27 May 2025
According to the study authors, the metabolites AMP and histidine were probably responsible for the signal of death that the C. elegans worms recognized.
—Sam Walters, Discover Magazine, 23 May 2025
High-quality protein is any protein that contains all of the nine essential amino acids (histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine) that our bodies don’t make on their own.
—USA TODAY, 2 July 2023
While some groups benefit from B12 and folate supplementation, less is known about L-histidine supplementation.
—Tamar Kane, Verywell Health, 5 Feb. 2023
This essential amino acid can help treat premature ejaculation by delaying the conversion of histidine into histamine in your body.
—Dallas News, 23 Dec. 2022
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Stacey Colino, Time, 27 May 2025
According to the study authors, the metabolites AMP and histidine were probably responsible for the signal of death that the C. elegans worms recognized.
—Sam Walters, Discover Magazine, 23 May 2025
High-quality protein is any protein that contains all of the nine essential amino acids (histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine) that our bodies don’t make on their own.
—USA TODAY, 2 July 2023
While some groups benefit from B12 and folate supplementation, less is known about L-histidine supplementation.
—Tamar Kane, Verywell Health, 5 Feb. 2023
This essential amino acid can help treat premature ejaculation by delaying the conversion of histidine into histamine in your body.
—Dallas News, 23 Dec. 2022
Cite this Entry
“Histidine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/histidine. Accessed 9 Sep. 2025.
Copy CitationMedical Definition
histidine
noun
his·ti·dine
ˈhis-tə-ˌdēn
: a crystalline essential amino acid C6H9N3O2 formed by the hydrolysis of most proteins
—abbreviation His
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