How to say "gruesome" in Japanese

• 凄惨せいさん
  na-adjective, nounThe closest match for the core sense of gruesome: ghastly, appalling, lurid. It describes horrifying scenes or events, such as a ghastly accident or disaster, and is a less common word.
• 身の毛のよだつみのけのよだつ
  expression, godan verbReally means hair-raising or bloodcurdling — so horrible your hair stands on end. For gruesome it is only a partial fit: it conveys the horrified reaction rather than the ghastly scene itself, and is less common.
  それは身の毛みのけのよだつ思おもいだよ。↗

  That's a hair-raising thought.
• ものすごいJLPT N2approx.Common
  i-adjectiveA common word, usually written in kana, meaning frightful, horrific or terrible. It covers gruesome only loosely — it often just means tremendous — so it suits general emphasis rather than precise description.
  ものすごい叫び声さけびごえに彼かれはぞっとした。↗

  The sound of an awful scream made him shudder.

Choose 凄惨 for ghastly, gruesome scenes, 「身の毛のよだつ」 when gruesome means hair-raising or bloodcurdling, and 「ものすごい」 as the common, general word — broader and vaguer than the other two.

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

• 凄惨せいさんghastly
• 身の毛のよだつみのけのよだつhair-raising
• ものすごいfrightful