Ansatsuken

Ansatsuken (暗殺拳, literally "assassination fist") is a Japanese neologism used frequently in fictional works to describe any martial art style or fighting technique that has been developed with the purpose of killing an opponent. The term satsujinken (殺人拳, literally "murderous fist") is used interchangeably as well and the homophonous term satsujinken (殺人剣, literally "murderous sword") is used when the martial art style or technique explicitly revolves around swordsmanship rather than barehanded combat.