treated as a daughter; adopted daughter figure
Refers to a girl or woman who is treated like one's own daughter, often in a non-biological, familial or mentor-like relationship. Can also describe the act of treating someone as a daughter.
彼女は師匠の娘分として大切に育てられた。
She was raised with great care as her master's daughter figure.
あの子は私にとって娘分のような存在だ。
That child is like a daughter to me.
geisha house manager (Edo period)
Archaic term for a woman who managed geisha in the Edo period. Not used in modern Japanese.
江戸時代の遊郭では、娘分が芸者たちの世話をしていた。
In the pleasure quarters of the Edo period, the 'musumebun' took care of the geisha.
Compound of 娘 (musume, 'daughter') and 分 (bun, 'part' or 'role'), literally 'daughter role'. The archaic geisha-related sense likely developed from the idea of a woman acting in a maternal or managerial role over younger geisha.