anxiety

1. Origins, structure, and basic meaning

• Structure: 愁 has 13 strokes, the on-reading しゅう, and the kun-readings うれえる and うれい. 哀愁 (あいしゅう) and 愁い (うれい) express sorrow or anxiety.
• Basic usage: 哀愁 means melancholy felt in something such as a sound or scene; 愁い means sorrow or anxiety held in the heart.

2. Common pitfalls and similar expressions

• Melancholy and the depth of sorrow
  • 静かな哀愁が漂っていた describes gentle melancholy in the sound of a flute. 哀愁を感じた means that someone felt wistfulness in a painting of a harbor at sunset.
  • 深い愁い refers to deep anxiety shown in someone's profile. 淡い愁い describes the faint sorrow in a song about an autumn evening.