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
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Amino acids in miso, such as glutamate and histidine, may help your stomach empty itself and reduce potential discomfort after meals, said Jennifer Pallian, BSc, RD, a registered dietitian and founder of Foodess.
—
Kathleen Ferraro, Verywell Health, 19 Dec. 2025
While in this energized state, the lignin functions as a photoacid, transferring protons to the histidine inside the solid material.
—Mrigakshi Dixit, Interesting Engineering, 10 Nov. 2025
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
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Kathleen Ferraro, Verywell Health, 19 Dec. 2025
While in this energized state, the lignin functions as a photoacid, transferring protons to the histidine inside the solid material.
—Mrigakshi Dixit, Interesting Engineering, 10 Nov. 2025
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
Cite this Entry
“Histidine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/histidine. Accessed 27 Mar. 2026.
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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