Ulceration n. : The process of forming an ulcer, or of becoming ulcerous; the state of being ulcerated; also, an ulcer.

Example:
How to treat Ulceration of the choana in a moustache parakeet?

Taxonomy
Ulceration, free encyclopedia, discontinuity, Ulcer, stomach ulcer, search, free dictionary, medicine, skin, open sore, mouth, gastrointestinal mucosa, infective, cornea, wound, valves, veins, American.

Defination from the web:
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