How to say "debacle" in Japanese

• 敗走はいそうCommon
  noun, suru verb, intransitive verbCovers 'debacle' as a rout: a defeat so crushing that it turns into flight. It is really the word for breaking and running in defeat, not for a plan or project that fails.
  ドイツ軍ぐんは敗走はいそうした。↗

  The Germans took to flight.
• 大失敗だいしっぱい
  noun, suru verb, transitive verb, intransitive verbCovers 'debacle' in the sense of a fiasco: a plan or undertaking that fails completely, a disaster. For this 'complete failure' sense it is the word you want, though a less common one.
  さっきの手ては大だい失敗しっぱいだった。↗

  That move was a big mistake.

Use 敗走 for a debacle that is a rout — a crushing defeat ending in flight; use 大失敗 for a debacle that is a fiasco, an undertaking or plan that fails completely.

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

• 敗走はいそうflight
• 大失敗だいしっぱいcomplete failure