How to say "regret" in Japanese

• 後悔こうかいJLPT N1approx.Common
  suru verb, transitive verb, intransitive verb, no-adjectiveThe default choice for regret over something one has done or failed to do; it centers on remorse about one's own past actions or decisions, as in looking back and wishing one had chosen differently.
  今更いまさら後悔こうかいしても無駄むだだ。↗

  It's no use regretting it now.
• 無念むねんJLPT N1approx.Common
  na-adjective, no-adjectiveCovers regret as bitter chagrin or mortification over an outcome, typically losing or falling short; the feeling is disappointment and frustration rather than remorse over one's own conduct.
• 悔いくいCommon
  nounA noun covering regret and repentance, often for a lasting or deep-seated feeling left behind by events; suited to speaking of regret that remains, including remorse over one's own deeds.
  我わが生涯しょうがいに一いち片へんの悔くいなし。↗

  I regret nothing of my life.
• 悲しむかなしむJLPT N3approx.Common
  godan verb, transitive verbPrimarily 'to be sad' or 'to mourn for', with 'to regret' only as a minor sense; it is seldom the word you want for remorse, and fits when 'regret' really means feeling sorrow over something.
  悲かなしんでいる彼女かのじょをそっとしておきなさい。↗

  Do not obtrude upon her sorrow.
• 嘆くなげくJLPT N1approx.Common
  godan verb, transitive verb, intransitive verbPrimarily 'to lament' or 'to grieve', with 'to regret' as a marginal sense; use it when the meaning is lamenting or sorrowing over a situation, not when expressing remorse about one's own actions.
  「財布さいふを無なくした」ジョンは嘆なげいた。↗

  "I lost my wallet," lamented John.

Use 後悔 for regret over one's own actions, 無念 for bitter disappointment at an outcome, 「悔い」 for lasting remorse, and 「悲しむ」 or 「嘆く」 only when 'regret' means sorrow or grieving rather than remorse.

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

• 後悔こうかいregret
• 無念むねんregret
• 悔いくいregret
• 悲しむかなしむto be sad
• 嘆くなげくto lament
• 未練みれんlingering attachment
• 悔いるくいるto regret
• こころのこりregret
• 思い残すおもいのこすto regret
• 哀悼あいとうcondolence
• うらむto regret
• 悔恨かいこんregret
• リグレットregret
• 慨するがいするto regret
• 無念がるむねんがるto regret
• 遺憾の意いかんのいregret
• 慨嘆がいたんdeploring
• 惜しげおしげreluctance
• 気の毒に思うきのどくにおもうto feel sorry (for, that)
• 残念に思うざんねんにおもうto repent
• 悔しさくやしさchagrin
• 側むそばむto lean to one side
• 反省はんせいregret
• 惜しむおしむto regret
• 恨みうらみmatter for regret
• 悔やむくやむto be sorry
• 残心ざんしんlingering affection