histidine

noun

his·​ti·​dine ˈhi-stə-ˌdēn How to pronounce histidine (audio)
: a crystalline essential amino acid C6H9N3O2 formed by the hydrolysis of most proteins

Examples of histidine in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
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 The other six essential amino acids required to build and repair muscle are histidine, lysine, methionine, phenylalanine, threonine, and tryptophan. — Shimite Obialo, Forbes.com, 26 May 2026 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 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 See All Example Sentences for histidine

Word History

Etymology

International Scientific Vocabulary hist- + -idine

First Known Use

1896, in the meaning defined above

Time Traveler
The first known use of histidine was in 1896

Rhymes for histidine

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Browse Nearby Words

histi-
histidine
histie
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Cite this Entry

“Histidine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/histidine. Accessed 7 Jul. 2026.

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Medical Definition

histidine

noun
his·​ti·​dine ˈhis-tə-ˌdēn How to pronounce histidine (audio)
: a crystalline essential amino acid C6H9N3O2 formed by the hydrolysis of most proteins
—abbreviation His

More from Merriam-Webster on histidine

Britannica.com: Encyclopedia article about histidine

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