evil · bad

1. Origins, structure, and basic meaning

• Structure: 悪 has 11 strokes, the on-reading あく, and the kun-readings わるい and わる. 悪い (わるい) means bad; 悪化 (あっか) has っ in its reading.
• Basic usage: 悪い describes an unfavorable condition or being at fault; 悪化 names a change for the worse in a situation or relationship.

2. Common pitfalls and similar expressions

• A bad condition and a change for the worse
  • 天気が悪い means that the weather is bad. 約束を忘れたのは私が悪かった acknowledges that forgetting the promise was the speaker's fault.
  • 情勢が悪化する means that the situation worsens. 二人の関係の悪化 refers to the deterioration of the relationship between two people.