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evil; wickedness
(role of) the villain (in theatre, etc.); the bad guy
「悪」 has another reading with different meanings.
彼は悪の道に進んでしまった。
He went down the path of evil.
善と悪の区別をしっかりつけよう。
Let's distinguish good from evil.
この物語では最後に悪が滅びて正義が勝つ。
In this story, evil is destroyed and justice wins in the end.