noun
bast
Botanical term for the fibrous material from the inner bark of certain plants, used in textiles and cordage.
靭皮は繊維が強く、縄や布に加工される。
Bast has strong fibers and is processed into rope and cloth.
The term 靭皮 (じんぴ) is a Sino-Japanese compound: 靭 (じん, 'tough, pliable') + 皮 (ひ, 'skin, bark'). It refers to the tough inner bark layer of plants.