sever · decide

1. Origins, structure, and basic meaning

• Structure: 断 has 11 strokes; 断つ is read たつ, and 断る is read ことわる.
• Basic usage: 断つ means breaking or cutting off something that continues; 断る means refusing or giving advance notice.

2. Common pitfalls and similar expressions

• Breaking something off and giving notice
  • 悪い習慣を断つ means breaking a bad habit. 断ちました, used where snow cuts off a road, is an inflected form of the same verb 断つ.
  • 誘いを丁寧に断った describes politely refusing an invitation. By contrast, 一言断る before taking a photograph means giving a brief advance notice, so 断る does not mean refusal in every context.