noun Date: circa 1596 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
CANKER SORE
Meaning of CANKER SORE in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012