A sore in the lining of the esophagus, stomach, or duodenum, usually caused by the bacterium Helicobacter pylori. An ulcer in the stomach is a gastric ulcer; an ulcer in the duodenum is a duodenal ulcer.
A sore in the lining of the esophagus, stomach, or duodenum, usually caused by the bacterium Helicobacter pylori. An ulcer in the stomach is a gastric ulcer; an ulcer in the duodenum is a duodenal ulcer.