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N3Lesson notes · Oct 4, 2026

Justice in Japanese: 正義せいぎ (せいぎ), 正義せいぎの味方みかた, 正義感せいぎかん, 公平こうへい, and ずるい

"Justice" in Japanese is 正義せいぎ (せいぎ), literally "right principle". A hero who fights for justice is a 正義せいぎの味方みかた (せいぎのみかた), "an ally of justice", and a strong sense of right and wrong is 正義感せいぎかん (せいぎかん). In everyday life, "fair" is 公平こうへい (こうへい), and the casual complaint "no fair!" is ずるい!

正義せいぎ is a dramatic word, heavy with anime and superhero energy, and also a serious word in law and ethics. Day to day, Japanese people talk about fairness more than justice, using words like 公平こうへい and ずるい. This post covers both the grand and the everyday vocabulary of what's right.

How do you say "justice" in Japanese?

What does 正義せいぎ mean?

正義せいぎ (せいぎ) is justice, what is morally right. It sounds serious or dramatic.

正義せいぎのために戦たたかう。 — I fight for justice. (dramatic) 正義せいぎは必かならず勝かつ。 — Justice always wins. (dramatic)

For heroes, see hero in Japanese.

What is 正義せいぎの味方みかた?

正義せいぎの味方みかた (せいぎのみかた), "an ally of justice", is a hero who fights for what's right, a classic phrase from tokusatsu and anime.

子こどものころ、正義せいぎの味方みかたになりたかった。 — As a kid, I wanted to be a hero of justice. (casual)

What is 正義感せいぎかん?

正義感せいぎかん (せいぎかん) is a sense of justice, a strong feeling for right and wrong.

彼女かのじょは正義感せいぎかんが強つよい。 — She has a strong sense of justice. (casual)

How do you talk about fairness?

What does 公平こうへい mean?

公平こうへい (こうへい) means fair or impartial. 不公平ふこうへい (ふこうへい) is unfair.

みんなに公平こうへいにお菓子かしを分わけた。 — I shared the snacks fairly with everyone. (casual) それは不公平ふこうへいだ。 — That's unfair. (casual)

What does ずるい mean?

ずるい means sneaky, unfair or "no fair!". It is a very common casual complaint, often playful.

ずるい!私わたしもほしい! — No fair! I want one too! (casual)

For 汚きたない as "dirty, unfair", see dirty in Japanese.

What does 正ただしい mean?

正ただしい (ただしい) means correct or right. 正ただしいことをする is "to do the right thing".

正ただしいことをしたと思おもう。 — I think I did the right thing. (casual)

Word Reading Meaning
正義せいぎ せいぎ justice
正義せいぎの味方みかた せいぎのみかた hero of justice
正義感せいぎかん せいぎかん sense of justice
正ただしい ただしい correct, right
公平こうへい こうへい fair
不公平ふこうへい ふこうへい unfair
ずるい ずるい sneaky, no fair
悪あく あく evil

Beyond the basics

What is the opposite of 正義せいぎ?

The opposite is 悪あく (あく), evil. 正義せいぎと悪あく is "good and evil", the classic hero-versus-villain theme.

正義せいぎと悪あくの戦たたかい。 — The battle between good and evil. (dramatic)

What does 正義せいぎの反対はんたいはまた別べつの正義せいぎ mean?

A well-known idea in Japanese pop culture is that the opposite of justice is not evil but another kind of justice: each side believes it is right.

正義せいぎの反対はんたいは、また別べつの正義せいぎだ。 — The opposite of justice is just another kind of justice. (reflective)

What is 裁判さいばん?

裁判さいばん (さいばん) is a trial or court case, where legal justice is decided. 裁判所さいばんしょ is a courthouse.

事件じけんは裁判さいばんになった。 — The case went to trial. (casual)

What does 筋すじが通とおる mean?

筋すじが通とおる (すじがとおる), "the thread runs through", means something is logical and fair, it makes sense. 筋すじが通とおらない is "it doesn't add up" or "that's not right".

その説明せつめいは筋すじが通とおっている。 — That explanation makes sense. (casual) そんなの筋すじが通とおらない。 — That's just not right. (casual)

What is 正当せいとう?

正当せいとう (せいとう) means legitimate or justified: 正当せいとうな理由りゆう is a legitimate reason, and 正当防衛せいとうぼうえい (せいとうぼうえい) is self-defense.

正当せいとうな理由りゆうがあれば休やすめる。 — You can take time off if you have a legitimate reason. (casual)

Common mistakes

  • Using 正義せいぎ for small daily fairness. For sharing snacks, say 公平こうへい.
  • Reading 正義せいぎ as しょうぎ. It is せいぎ.
  • Thinking ずるい is always harsh. It is often playful.
  • Reading 公平こうへい as こうひら. It is こうへい.
  • Saying 正義せいぎの友ともだち for "hero of justice". The phrase is 正義せいぎの味方みかた.

Practice

Try each answer before opening it. Questions 3 and 4 are a pair: fair versus unfair.

1. Say dramatically, "Justice always wins."

Show answer

正義せいぎは必かならず勝かつ。 — 正義せいぎ.

2. Say "As a kid, I wanted to be a hero of justice."

Show answer

子こどものころ、正義せいぎの味方みかたになりたかった。 — 正義せいぎの味方みかた.

3. Say "I shared the snacks fairly with everyone."

Show answer

みんなに公平こうへいにお菓子かしを分わけた。 — 公平こうへい.

4. Say "That's unfair."

Show answer

それは不公平ふこうへいだ。 — 不公平ふこうへい. This is the pair to question 3.

5. Your sibling got a treat and you didn't. Complain playfully.

Show answer

ずるい!私わたしもほしい! — ずるい.

6. Say "She has a strong sense of justice."

Show answer

彼女かのじょは正義感せいぎかんが強つよい。 — 正義感せいぎかん.

7. Say "I think I did the right thing."

Show answer

正ただしいことをしたと思おもう。 — 正ただしい.

8. Say "The battle between good and evil."

Show answer

正義せいぎと悪あくの戦たたかい。 — 正義せいぎと悪あく.

9. Say "The case went to trial."

Show answer

事件じけんは裁判さいばんになった。 — 裁判さいばん.

10. How do you read 正義せいぎ?

Show answer

せいぎ — not しょうぎ.

FAQ

How do you say "justice" in Japanese? 正義せいぎ (せいぎ).

What is 正義せいぎの味方みかた? A hero who fights for justice.

How do you say "fair"? 公平こうへい (こうへい).

What does ずるい mean? Sneaky or "no fair!".

What is the opposite of 正義せいぎ? 悪あく (あく), evil.

What is 正義感せいぎかん? A sense of justice.

Vocabulary from this article

Tap the block to select all of it, then copy. In Anki: File → Import, note type Basic, separator Tab — the first column becomes the front, the second the back.

正義	せいぎ — justice
正義の味方	せいぎのみかた — hero of justice
正義感	せいぎかん — sense of justice
正しい	ただしい — correct, right
公平	こうへい — fair
不公平	ふこうへい — unfair
ずるい	ずるい — sneaky, unfair
悪	あく — evil
裁判	さいばん — trial
戦う	たたかう — to fight
筋が通る	すじがとおる — to make sense
正当	せいとう — legitimate

I'm Yuuki, a Japanese teacher based in Tokyo. I've taught on italki as a Top 1% teacher and watched over 1,500 anime. 正義せいぎの味方みかた is the phrase anime fans recognize instantly, and ずるい is the everyday version of justice, the word kids use when something feels unfair. For practice with feedback, Book a trial lesson · $13, or try the Japanese practice exercises first.

Sources: the author's own lessons and standard reference dictionaries.

More drills like the ones above, plus a timed JLPT-style mock test: Practice · N3 · Read something at this level: JLPT N3 stories with audio

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