enemy

1. Origins, structure, and basic meaning

• Structure: 敵 has 15 strokes and the on-reading てき. 敵 (てき) means an enemy; 素敵 (すてき) describes something wonderful or lovely.
• Basic usage: 敵 is used for opponents and harmful factors. 素敵 gives a positive assessment of things such as rooms or letters.

2. Common pitfalls and similar expressions

• Enemies and positive evaluations
  • 強大な敵に立ち向かった means confronting a powerful enemy. 睡眠不足は集中力の敵だ figuratively presents lack of sleep as an enemy of concentration.
  • 素敵な部屋 and 素敵な手紙 mean a wonderful room and a lovely letter. 素敵 as a whole expresses praise, so it cannot be understood from 敵 alone.