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canker sore

noun

Definition of canker sore

  1. :  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

See canker sore defined for English-language learners

See canker sore defined for kids

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First Known Use of canker sore

circa 1596

CANKER SORE Defined for English Language Learners

canker sore

noun

Definition of canker sore for English Language Learners

  • : a small painful sore inside the mouth

CANKER SORE Defined for Kids

canker sore

noun can·ker sore \ˈkaŋ-kər-\

Definition of canker sore for Students

  1. :  a small painful sore of the mouth

Medical Dictionary

canker sore

noun

Medical Definition of canker sore

  1. :  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

Learn More about canker sore

  1. See words that rhyme with canker sore Britannica.com: Encyclopedia article about canker sore

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