noun
inner layer of clothing; inner garment (not underwear)
Refers to a middle layer worn between underwear and outerwear, such as a shirt or blouse. Often used in contrast with 上衣 (outer layer) and 下衣 (underwear).
寒い日は、下着の上に中衣を重ね着する。
On cold days, I layer an inner garment over my underwear.
中衣は肌に直接触れないので、素材を選びやすい。
Since the inner layer doesn't touch the skin directly, it's easy to choose the material.