The definition of an ulcer is an open sore on the surface of the skin or inside the body in a mucous membrane.(noun)
An example of an ulcer is a sore in the stomach lining caused by a bacterial infection.
See ulcer in Webster's New World College Dictionary
Origin: L ulcus (gen. ulceris) < IE *elkos-, abscess > Sans árśas-, hemorrhoids, Gr helkos, abscess, wound
See ulcer in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old French ulcere
Origin: , from Latin ulcus, ulcer-.
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