treacherous retainer; rebellious vassal
Historical term for a vassal or retainer who betrays their lord, often in the context of feudal Japan. Rare in modern conversation except when discussing history or period dramas.
During the Warring States period, there were many cases of treacherous retainers betraying their lords.
逆臣 is a treacherous vassal who betrays their lord, the direct opposite of a loyal 忠臣.
Compound of 逆 (gyaku, 'reverse; contrary') and 臣 (shin, 'retainer; subject'). The term follows classical Chinese-influenced word formation.