1An ulcer: an area of tissue breakdown on skin or mucous membranes; medically often refers to ulcers in organs like the stomach or intestines.
医師は胃潰瘍の疑いがあるとして検査を勧めた。
The doctor suspected a gastric ulcer and recommended tests.
口内に小さな潰瘍ができて食事がつらい。
I have a small ulcer in my mouth and eating is painful.