Ulcer n. : A solution of continuity in any of the soft parts of the body, discharging purulent matter, found on a surface, especially one of the natural surfaces of the body, and originating generally in a constitutional disorder; a sore discharging pus. It is distinguished from an abscess, which has its beginning, at least, in the depth of the tissues.

Ulcer n. : Fig.: Anything that festers and corrupts like an open sore; a vice in character.

Ulcer v. t. : To ulcerate.

Example:
What are the symptoms of a stomach Ulcer?

Taxonomy
ulcer, peptic ulcer, duodenal ulcers, gastric ulcers, stomach, H. pylori, NSAIDs, EGD, infection, stress, peptic ulcer disease, Treatment, Helicobacter pylori, Marshall, meal, PMID, perforation, H. pylori infection.

Defination from the web:
ulcer. Medicines associated with peptic ulcer include NSAID (non-steroid anti-inflammatory drugs) that inhibit cyclooxygenase, and most glucocorticoids ...