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chamberlain
侍従が天皇陛下の到着を告げた。
The chamberlain announced the Emperor's arrival.
彼は長年、宮内庁の侍従を務めた。
He served as a chamberlain for the Imperial Household Agency for many years.
侍従は厳格な儀礼と絶対的な守秘義務を守る。
A chamberlain observes strict protocol and absolute discretion.