small intestine
Anatomical term for the part of the digestive tract between the stomach and large intestine.
小腸は栄養の吸収を担っている。
The small intestine is responsible for absorbing nutrients.
小腸 names specifically the small intestine, whereas 腸 is the general anatomical term covering all the intestines.
From 小 (small) + 腸 (intestine).