noun
ogre extermination; demon slaying; chasing out ogres
Refers to the act of driving away or destroying ogres (oni), often in folklore, fairy tales, or metaphorical contexts.
桃太郎は鬼退治に出かけた。
Momotaro set out to exterminate the ogres.
この昔話は鬼退治の物語です。
This folk tale is a story of ogre slaying.
退治 means extermination or suppression in general; 鬼退治 specifies the target as ogres.
Compound of 鬼 (oni, 'ogre') and 退治 (taiji, 'extermination'). The exact historical derivation is straightforward; the term is commonly used in folklore contexts.