How to say "deed" in Japanese

Choosing the right word

行為こういJLPT N1approx.Common
nounCovers 'deed' as an act or conduct in a neutral, somewhat formal way, e.g. a criminal or heroic deed. The safest choice when describing an action without judging it.
彼かれは自分じぶんの行為こういを正当化せいとうかしようとしている。↗
He is trying to justify his act.
行いおこないJLPT N1approx.Common
nounDeed or act with a personal, often moral flavor — how one behaves, good deeds and bad deeds alike. Typical of talk about someone's conduct in everyday life.
彼かれは勇気ゆうきある行おこないをした。↗
He did a courageous act.
仕業しわざCommon
nounA deed as someone's doing, usually negative — a wicked or mischievous act attributed to a person. Use it when blaming or identifying who is behind a bad deed.
それ、ウィルスの仕業しわざじゃないかな。↗
That looks like the work of a virus.
所業しょぎょうCommon
nounAn act or deed, usually an undesirable one; often refers to a deed that is criminal, cruel or otherwise blameworthy. Suited to denouncing someone's deed.
証文しょうもんCommon
nounNot a deed as an act: this word means a bond, deed or contract as a legal document. It is only the word you want for 'deed' in the property-law sense.

For 'deed' as an act, choose 行為 or 「行い」 (「行い」 more personal/moral); 仕業 and 所業 for (bad) deeds someone did; 証文 only for the legal document sense.

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

Japanese equivalents

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