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chief vassal; senior statesman
将軍は重臣を深く信頼した。
The shogun deeply trusted his chief vassal.
幕府の重臣たちが緊急会議を開いた。
The shogun's chief vassals held an emergency meeting.
幼い将軍のもとで重臣たちが実権を握った。
Under the young shogun, the chief vassals seized real power.