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spirit of rebellion
家臣の叛意を察知した領主は先手を打った。
The lord sensed his vassal's rebellious intent and struck first.
叛意を隠しながら表面上は忠誠を装った。
While concealing their rebellious intent, they pretended loyalty on the surface.
軍内部に叛意が芽生えていることが判明した。
It was discovered that rebellious sentiment was growing within the military.