How to say "effect" in Japanese

• 効果こうかJLPT N3approx.Common
  no-adjectiveThe general word for an effect as a result produced by an action, treatment or measure; it also covers effectiveness and efficacy, fitting talk of whether a medicine, policy or training works.
  彼かれらがいくら弁解べんかいしても彼女かのじょには何なんの効果こうかもなかった。↗

  Their excuses cut no ice with her.
• 影響えいきょうJLPT N3approx.Common
  noun, suru verb, intransitive verbThe word for effect in the sense of influence: how one thing affects a person, situation or system. Choose it for effects on health, the environment or the economy, whether good or bad.
  多おおくのテレビ番組ばんぐみが子供こどもたちに悪わるい影響えいきょうを与あたえている。↗

  Many TV programs have a bad influence on children.
• インパクトCommon
  nounLoanword for impact: a strong, striking effect or the powerful impression something makes. Seldom the word for an ordinary effect; use it when the point is force or how striking something is.
  あのコマーシャルってインパクト強つよいね。特とくに、音楽おんがくが耳みみに残のこるよ。↗

  That commercial makes a strong impression - especially the music. It stays in your head.
• 効能こうのうCommon
  nounThe efficacy of medicines, cosmetics and health products — the beneficial effects they are claimed to have. Seldom a general substitute for effect; think of product descriptions and health claims.
  絵画かいがが有ゆうする第だい一いちの効能こうのうは見みる人ひとの目めのごちそうとなることである。↗

  The first virtue of a painting is to be a feast for the eyes.
• 効力こうりょくJLPT N2approx.Common
  nounEffect as force or validity: the effect a law or contract has, including coming into effect, and the potency of a medicine; the word for legal effect.
  その法律ほうりつはもう効力こうりょくはなくなっている。↗

  The law is not in effect any longer.

Choose 効果 for an effect as an achieved result, 影響 for effects as influence on something, 効能 for the efficacy of medicines and health products, 効力 for legal force or potency, and 「インパクト」 for a striking impact or impression.

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

• 効果こうかeffect
• 影響えいきょうinfluence
• インパクトimpact (on)
• 効能こうのうeffect
• 効力こうりょくeffect
• 効き目ききめeffect
• 結果けっかresult
• 出来栄えできばえresult
• 効用こうようuse
• 作用さようaction
• 甲斐かいresult (that makes an act worthwhile)
• 趣旨しゅしmeaning
• 効こうefficacy
• エフェクトeffect
• 効験こうけんefficacy
• 出来具合できぐあいresult
• 甲斐がいresult (that makes an act worthwhile)
• ためconsequence
• 力ちからefficacy
• 関係かんけいinfluence
• 反応はんのうreaction
• 趣おもむきeffect
• 験げんeffect (e.g. of prayers; as the result of intense training)
• 詮せんeffect
• 手応えてごたえresponse (to one's efforts)
• 回りまわりeffect