cystine

noun

cys·​tine ˈsi-ˌstēn How to pronounce cystine (audio)
: a crystalline amino acid C6H12N2O4S2 that is widespread in proteins (such as keratins) and is a major metabolic sulfur source

Examples of cystine in a Sentence

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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.
Drinking enough water is the most important lifestyle factor for cystine stones.6 Can Sparkling Water Cause Kidney Stones? Assessing Risks to Avoid Kidney Stones Kidney stones may affect one in 10 in the U.S., but their presentation can vary quite widely. — Julia Landwehr, Health, 4 Aug. 2023 But the drug that dragged cystine to the surface also altered the overall shape of the peptide, Shokat explains, and that raised the question of whether the altered molecule could still attach to MHC molecules. — Connor Lynch, Discover Magazine, 26 Oct. 2022

Word History

Etymology

from its discovery in bladder stones

First Known Use

1843, in the meaning defined above

Time Traveler
The first known use of cystine was in 1843

Rhymes for cystine

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Cite this Entry

“Cystine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cystine. Accessed 11 Mar. 2025.

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Medical Definition

cystine

noun
cys·​tine ˈsis-ˌtēn How to pronounce cystine (audio)
: an amino acid C6H12N2O4S2 that is a dimer of cysteine, is widespread in proteins (as keratins), and is a major metabolic sulfur source

More from Merriam-Webster on cystine

Britannica.com: Encyclopedia article about cystine

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