Educational Content: This article is for informational purposes only and does not constitute medical advice. Always consult a healthcare provider for diagnosis and treatment.
Definition of Canker sore
Medically reviewed by Min Clinic Staff | Updated: January 2026
Canker sore: A common small, frequently painful and sensitive crater in the lining of the mouth. Also known as aphthous ulcer. Sores typically last for 10 to 14 days and generally heal without scarring.