1. mouth ulcer; stomatitis
Wikipedia definition
2. Mouth ulcerA mouth or oral ulcer is an open sore in the mouth, or rarely a break in the mucous membrane or the epithelium on the lips or surrounding the mouth. The types of mouth ulcers are diverse, with a multitude of associated causes including: physical abrasion, acidic fruit, infection, other medical conditions, medications, and cancerous and nonspecific processes. Once formed, the ulcer may be maintained by inflammation and/or secondary infection.
Read “Mouth ulcer” on English Wikipedia
Read “口内炎” on Japanese Wikipedia
Read “Mouth ulcer” on DBpedia


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