ULCER By Nugent, Pam M.S. - April 29, 2013 noun. an erosion of a tissue's exterior, like the digestive tract's mucosal lining. ULCER: "The patient is suffering from symptoms of a peptic ulcer." Related Psychology Terms GASTRODUODENAL ULCERATION INTRAVENOUS INJECTION (IV INJECTION) TOPICAL APPLICATION UNIPOLAR STIMULATION ABLATION MOTILITY DISORDER MYENTERIC PLEXUS SECRETIN VIBRATION RECEPTOR INTEROCEPTIVE CONDITIONING Cite this page: Nugent, Pam M.S., "ULCER," in PsychologyDictionary.org, April 29, 2013, https://psychologydictionary.org/ulcer/ (accessed June 28, 2017).