How to say "madman" in Japanese

• キチガイCommon
  nounCovers both the condition (madness, insanity) and the person (madman, lunatic). Strongly derogatory and sensitive, it is the word heard as an insult — avoid it unless you mean to offend. Usually written in kana alone.
  デルバートは気違きちがいだと思おもうよ。↗

  I think that Delbert is crazy.
• 狂人きょうじんCommon
  no-adjectiveRefers to a lunatic or madman, a person who is insane. Unlike キチガイ it carries no strongly derogatory charge, so it is the safer choice when you simply mean 'a madman'.
  その囚人しゅうじん達たちはまるで狂人きょうじんのように互たがいに争あらそった。↗

  The prisoners fought one another like so many mad people.

Both words can mean a madman, but 「キチガイ」 is a strongly derogatory, sensitive term that also covers madness and insanity itself, while 狂人 is a comparatively neutral word for a lunatic.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• きちがいmadness
• 狂人きょうじんlunatic
• キ印キじるしmadness
• ガイキチmadness