noun
younger pupil (of the same master); younger disciple; junior member
Refers to a junior disciple under the same teacher or master, often in traditional arts, crafts, or martial arts. Contrasts with 兄弟子 (older disciple).
See also: 兄弟子
彼は私の弟弟子で、同じ師匠に師事している。
He is my younger fellow disciple, studying under the same master.
弟弟子の面倒を見るのも兄弟子の役目だ。
Looking after the younger disciples is also the role of the senior disciple.