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flagship
提督は旗艦から全艦隊に命令を出した。
The admiral issued orders to the entire fleet from the flagship.
旗艦が先頭に立って港を出発した。
The flagship led the way out of the port.
この戦艦は艦隊の旗艦に選ばれた。
This battleship was chosen as the fleet's flagship.