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son (of others); boy; young master
green young man from a well-to-do family; young man innocent of the ways of the world
お坊ちゃんは元気ですか。
Is your son doing well?
お坊ちゃんだから世間知らずだ。
He's innocent because he's from a wealthy family.
お坊ちゃんが遊んでいる。
The young master is playing.