canker sore


Definition of canker sore

: a painful shallow ulcer of the mouth that has a grayish-white base surrounded by a reddish inflamed area and is of uncertain cause but is not due to the virus causing herpes simplex — compare cold sore

Examples of canker sore in a Sentence

Recent Examples on the Web

And the lack of those nutrients develops canker sores. The New Yorker, "Alexandria Ocasio-Cortez on the 2020 Presidential Race and Trump’s Crisis at the Border," 10 July 2019 The products--sold under brand names like Orajel and Chloraseptic, as well as store brands and generics--are often used for relief from sore throats, canker sores and other oral irritations, according to the FDA. Laura Mcknight,, "Teething gels pose 'serious risk' to babies, FDA warns," 23 May 2018 Most canker sores resolve on their own within one to two weeks. Roni Caryn Rabin, New York Times, "What Causes Canker Sores?," 16 Mar. 2018 Now, for the burning question: Is alum a miracle treatment for canker sores? Zahra Barnes, SELF, "Why Trying to Cure Canker Sores With Alum May Not Be Worth It," 12 Dec. 2017 Then, like an unsightly canker sore on the lips of its résumé, lives the measly four takeaways which leave them tied for second-worst in the NFL. Paul Dehner Jr.,, "Cincinnati Bengals notes: Turnovers a glaring gap," 26 Oct. 2017

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

circa 1596, in the meaning defined above

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Statistics for canker sore

Last Updated

14 Jul 2019

Look-up Popularity

Time Traveler for canker sore

The first known use of canker sore was circa 1596

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More Definitions for canker sore

canker sore


English Language Learners Definition of canker sore

US : a small painful sore inside the mouth

canker sore

can·​ker sore | \ ˈkaŋ-kər-\

Kids Definition of canker sore

: a small painful sore of the mouth

canker sore


Medical Definition of canker sore

: a small painful ulcer especially of the mouth especially : a painful shallow ulceration of the oral mucous membranes that has a grayish-white base surrounded by a reddish inflamed area and is characteristic of aphthous stomatitis — compare cold sore

More from Merriam-Webster on canker sore

Rhyming Dictionary: Words that rhyme with canker sore Encyclopedia article about canker sore

Comments on canker sore

What made you want to look up canker sore? Please tell us where you read or heard it (including the quote, if possible).


not constant or steady

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