ker·​a·​to·​sis | \ ˌker-ə-ˈtō-səs How to pronounce keratosis (audio) \
plural keratoses\ ˌker-​ə-​ˈtō-​ˌsēz How to pronounce keratoses (audio) \

Definition of keratosis

: an area of skin marked by overgrowth of horny tissue

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Other Words from keratosis

keratotic \ ˌker-​ə-​ˈtä-​tik How to pronounce keratotic (audio) \ adjective

Examples of keratosis in a Sentence

Recent Examples on the Web Unlike melanoma which is usually characterized by unusual moles, lumps and markings, actinic keratosis appears as small, dry, scaly or crusty patches of skin, according to the Skin Cancer Foundation. NBC News, "How to heal dry, chapped lips, according to dermatologists," 20 Feb. 2020 In this case, a common benign keratosis is being removed with Liquid Nitrogen, in addition to a Fraxel treatment. Chelsey Sanchez, Harper's BAZAAR, "Dermatologist Paul Jarrod Frank Reacts to the Internet's Most Debated Skin Questions," 15 Nov. 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 Pro tip: focus on your elbows and lower legs to prevent or erase the tiny, pimple-like bumps known as keratosis pilaris. Ashley Weatherford, The Cut, "Everything at Paula’s Choice Is on Sale Right Now," 13 June 2018 How to deal: Seborrheic keratosis usually requires a peel, cryotherapy (freezing), laser, and often a combination of these. Simone Kitchens, Glamour, "The Brown Girl’s Guide to Brown Spots," 14 Mar. 2018 Rupert Craven undergoes a biopsy of an actinic keratosis in Herfurt’s clinic. Karla Adam, Washington Post, "Britain braces for an exodus of E.U. doctors and nurses feeling hurt by Brexit," 4 Mar. 2018 Just make sure to use it every single day, or your KP (keratosis pilaris) will keep on coming back. Ruby Buddemeyer, Marie Claire, "Behold: The 5 Most Likely Causes for Those Random Red Spots on Your Skin," 14 Feb. 2018 The skin condition, seborrheic keratosis, affects more than 83 million Americans. Linda Loyd,, "Malvern biotech acquires St. Louis start-up to develop treatments for skin disorders," 8 Aug. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'keratosis.' 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 keratosis

1888, in the meaning defined above

History and Etymology for keratosis

borrowed from German Keratose, from Greek kerat-, kéras "horn" + German -ose -osis — more at kerato-

Note: The term was promulgated, if not introduced, by the German physician Hermann Lebert (1813-78) in Ueber Keratose, oder die durch Bildung von Hornsubstanz erzeugten Krankheiten und ihre Behandlung, Breslau, 1864.

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Time Traveler for keratosis

Time Traveler

The first known use of keratosis was in 1888

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Statistics for keratosis

Cite this Entry

“Keratosis.” Dictionary, Merriam-Webster, Accessed 6 Aug. 2020.

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More Definitions for keratosis


ker·​a·​to·​sis | \ ˌker-ə-ˈtō-səs How to pronounce keratosis (audio) \
plural keratoses\ -​ˌsēz How to pronounce keratoses (audio) \

Medical Definition of keratosis

1 : a disease of the skin marked by overgrowth of horny tissue
2 : an area of the skin affected with keratosis

Other Words from keratosis

keratotic \ -​ˈtät-​ik How to pronounce keratotic (audio) \ adjective

More from Merriam-Webster on keratosis

Rhyming Dictionary: Words that rhyme with keratosis Encyclopedia article about keratosis

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