• 愁いうれい — sorrow; sadness; melancholy
• 愁えるうれえる — to grieve; to worry; to be in distress
• 哀愁あいしゅう — melancholy; pathos
• 郷愁きょうしゅう — nostalgia; homesickness
• 孤愁こしゅう — lonely sorrow
• 悲愁ひしゅう — deep sadness; grief

This kanji is built around the idea of the heart. It expresses a quiet, lingering feeling — worry, sorrow, or melancholy. It’s often used for emotional atmosphere, like nostalgia or bittersweet sadness.