canker sore

noun

: 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

Preventing triggers and maintaining good oral hygiene can help reduce the frequency of canker sores. —Sarah Jividen, Health, 17 May 2025

Meet the common canker sore Usually a canker sore is nothing to write home about. —Matt Fuchs, TIME, 26 Feb. 2025

And the stress and the weakened immune system caused canker sores, sore throat, and on top of it, the airline lost my luggage! —Sydney Bucksbaum, EW.com, 24 Jan. 2025

Word History

First Known Use

circa 1596, in the meaning defined above

Rhymes for canker sore

• albacore
• alongshore
• antiwar
• anymore
• blastopore
• carnivore
• commodore
• dinosaur
• evermore
• furthermore
• guarantor
• herbivore

Kids Definition

canker sore

noun

: a small painful open sore especially of the mouth

Medical Definition

canker sore

noun

: 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