ker·​a·​ti·​tis | \ ˌker-ə-ˈtī-təs How to pronounce keratitis (audio) \
plural keratitides\ ˌker-​ə-​ˈti-​tə-​ˌdēz How to pronounce keratitis (audio) \

Definition of keratitis

: inflammation of the cornea of the eye

Examples of keratitis in a Sentence

Recent Examples on the Web After buying cat-eye lenses at a flea market, the 26-year-old man developed a severe, painful infection called Acanthamoeba keratitis. Beth Mole, Ars Technica, "Here’s why you should never use decorative contact lenses—in graphic pictures," 30 Oct. 2019 Acanthamoeba keratitis occurs when the amoeba makes its way onto a person's cornea. NBC News, "Woman nearly loses sight in one eye after wearing contacts in shower and pool," 17 July 2019 Many contact lens wearers are unaware of the risk of this infection, called Acanthamoeba keratitis. NBC News, "Woman nearly loses sight in one eye after wearing contacts in shower and pool," 17 July 2019 The warning comes from a new case report in the New England Journal of Medicine, which tells the story of a woman who, after swimming in her contact lenses, developed acanthamoeba keratitis, an infection that can impair your vision. Maggie O'neill,, "Swimming in Contact Lenses Can Cause Vision Loss—Here’s How," 17 July 2019 Actually, sleeping in your contacts (or misusing them in other ways, like not cleaning them properly) can lead to corneal inflammation called keratitis as a result of reduced oxygen flow, Dr. Maszczak says. Korin Miller, SELF, "5 Entirely Preventable Eye Injuries Doctors See Way Too Often," 1 Nov. 2018 This means that certain bacteria have been linked to certain diseases, like Sjogren’s Syndrome or bacterial keratitis. Scientific American, "Meet the Eye Microbiome," 23 June 2019 Combined with the fact that microorganisms and allergens build up on your lenses over time, this increases your risk of an eye infection like infectious keratitis. Korin Miller, SELF, "Is It Terrible to Wear the Same Contact Lenses for a Long, Long Time?," 19 Oct. 2018 Acanthamoeba keratitis happens due to a microbe that can hang out in tap water (and distilled water, too), stick to your contacts, and cause an infection. Korin Miller, SELF, "7 Dangerous Mistakes You’re Making With Your Contact Lens Case," 25 July 2018

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

1858, in the meaning defined above

History and Etymology for keratitis

probably borrowed from French kératite, from Greek kerat-, kéras "horn" + French -ite -itis — more at kerato-

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Time Traveler for keratitis

Time Traveler

The first known use of keratitis was in 1858

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Cite this Entry

“Keratitis.” Dictionary, Merriam-Webster, Accessed 14 Apr. 2021.

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More Definitions for keratitis


ker·​a·​ti·​tis | \ ˌker-ə-ˈtīt-əs How to pronounce keratitis (audio) \
plural keratitides\ -​ˈtit-​ə-​ˌdēz How to pronounce keratitis (audio) \

Medical Definition of keratitis

: inflammation of the cornea of the eye characterized by burning or smarting, blurring of vision, and sensitiveness to light and caused by infectious or noninfectious agents

called also corneitis

— compare keratoconjunctivitis

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