ker·​a·​tin | \ ˈker-ə-tən How to pronounce keratin (audio) \

Definition of keratin

: any of various sulfur-containing fibrous proteins that form the chemical basis of horny epidermal tissues (such as hair and nails)

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Other Words from keratin

keratinous \ kə-​ˈra-​tə-​nəs How to pronounce keratinous (audio) \ adjective

Examples of keratin in a Sentence

Recent Examples on the Web

The ravenous larvae then feed on their victims’ keratin, tissue and blood, eventually moving from the nares to feed externally on the developing birds. Brigit Katz, Smithsonian, "Parasites Are Ruining the Lovesongs of Darwin’s Finches," 13 June 2019 Maybelline's cult classic Falsies has been reformulated with pro-keratin fibers that coat each lash for an amplified, so-good-they-look-fake shape. Jenna Rennert, Vogue, "5 New Black Mascaras You Need in Your Life This Fall," 17 Aug. 2018 Melanocytes are responsible for making pigment and are found deep in the skin, [and] squamous cells compose the upper layer of the skin and produce keratin. Rebecca Dancer, Allure, "The American Cancer Society's Annual Report Reveals Melanoma Cases Continue to Rise," 5 Apr. 2019 Those are called keratosis pilaris (KP)—a genetic condition that causes a buildup of keratin in your pores—and sadly, they can’t be cured. Chloe Metzger, Marie Claire, "The 5 Truly Spectacular Beauty Products I'm Loving This Week," 3 Aug. 2018 The product also boasts an innovative bonding polymer, which, combined with the spirulina, mimics the coating of the keratin treatment. Jihan Forbes, Allure, "The IGK Good Behavior Smoothing Spray Is Like a Keratin Treatment in a Bottle," 28 July 2018 Another culprit behind crustiness, explains New York City podiatrist Krista Archer, is that some of us don't shed keratin as quickly as others. Sophie Wirt, Allure, "The 11 Best Foot Creams That Podiatrists and Pedicurists Recommend for Dry, Achy Feet," 14 May 2018 Pangolin scales contain keratin, a protein also found in rhino horn and human fingernails. Washington Post, "In South Africa, plans for a refuge for pangolins in peril," 16 June 2018 In modern birds, these corneocytes are fatty and keratin is loosely packed, allowing the birds to not only shed dandruff, but help them stay cool while doing energy-intensive activities like flying. Jason Daley, Smithsonian, "Dinosaurs Had Dandruff, Too," 30 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'keratin.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of keratin

circa 1849, in the meaning defined above

History and Etymology for keratin

borrowed from German Keratin, from Greek kerat-, stem of kéras "horn" + German -in -in entry 1 — more at kerato-

Note: The term was introduced by the German physician and chemist Johann Franz Simon (1807-43) in Handbuch der angewandten medizinischen Chemie, 1. Theil, Medizinisch-analytische Chemie (Berlin, 1840), p. 49.

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Statistics for keratin

Last Updated

19 Jun 2019

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Time Traveler for keratin

The first known use of keratin was circa 1849

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More Definitions for keratin


ker·​a·​tin | \ ˈker-ət-ən How to pronounce keratin (audio) \

Medical Definition of keratin

: any of various sulfur-containing fibrous proteins that form the chemical basis of horny epidermal tissues (as hair and nails) and are typically not digested by enzymes of the gastrointestinal tract — see pseudokeratin

More from Merriam-Webster on keratin

Britannica English: Translation of keratin for Arabic Speakers Encyclopedia article about keratin

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