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keratin

[ ker-uh-tin ]
/ ˈkɛr ə tɪn /
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noun
a fibrous, structural protein that is the principal constituent of hoofs, nails, claws, talons, bills, horn, hair, feathers, etc., and that is found in the outermost layers of skin.
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Origin of keratin

First recorded in 1840–50; kerat- + -in2
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use keratin in a sentence

British Dictionary definitions for keratin

keratin

ceratin

/ (ˈkɛrətɪn) /

noun
a fibrous protein that occurs in the outer layer of the skin and in hair, nails, feathers, hooves, etc
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for keratin

keratin
[ kĕrə-tĭn ]

Any of a class of tough, fibrous proteins that are the main structural component of hair, nails, horns, feathers, and hooves. Keratins are rich in sulfur-containing amino acids, especially cysteine. Individual keratin molecules are entwined helically around each other in long filaments, which are cross-linked by bonds between sulfur atoms on different chains. The twining and cross-linking produce strength and toughness.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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