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standard of revolt; banner of rebellion
部下が上司に反旗を翻した。
The subordinate raised the banner of revolt against the boss.
市民が独裁政権に反旗を掲げた。
Citizens raised the flag of rebellion against the dictatorship.
彼は組織の方針に反旗を翻す覚悟を決めた。
He resolved to revolt against the organization's policy.