Definition of keratin
: any of various sulfur-containing fibrous proteins that form the chemical basis of horny epidermal tissues (such as hair and nails)
keratinousplay \kə-ˈra-tə-nəs\ adjective
Recent Examples of keratin from the Web
The star ingredient is a human keratin protein (discovered by scientists researching regenerative medicine for injuries) that allegedly works to plump each individual strand.
And Eyeko’s tinted gel goes the extra mile, nourishing brows with a blend of ginko biloba and keratin while imparting a glossy, catch-the-light finish.
That’s unsurprising, since most of what makes up rhino horn, despite its majestic appearance, is keratin—the same non-therapeutic protein found in human hair and nails.
But unlike modern baleen whales, which use plates made of keratin to screen krill and other small organisms out of the water, M. selenensis had teeth and likely sucked up small creatures like shrimp or squid off the bottom of the ocean floor.
Rhino horn, to take one example, is considered helpful in treating blood disorders and even cancer, despite being largely composed of keratin, the ingestion of which is not much different from chewing one’s fingernails.
Also, while the black-and-white bristles volumize and lengthen, there’s the added plus of keratin and rice peptides that work to protect and strengthen.
Save the Rhino International says that rhinos use their horns, made mostly from keratin (which our fingernails are made of), to defend their territories and to protect calves from other rhinos and predators.
Pieces need to be protected from bright sunlight: Over time, exposure can cause the layers of keratin to separate and the horns to crack.
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.
Origin and Etymology of keratin
International Scientific Vocabulary
First Known Use: circa 1849See Words from the same year
Seen and Heard
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