noun
diverticulum
Medical term for a small pouch or sac protruding from the wall of a hollow organ, especially in the digestive tract.
大腸憩室は、大腸の壁にできる小さな袋状の突出です。
A colonic diverticulum is a small pouch-like protrusion that forms in the wall of the large intestine.
憩室炎 (diverticulitis) is the inflammation of a diverticulum, whereas 憩室 refers to the pouch itself.
From 憩 (rest, recess) and 室 (chamber, room), likely a calque from Western medical terminology.