痛憾

1. Origins, structure, and basic meaning

• Structure: 痛憾, read つうかん, denotes profound, formal regret concerning a serious outcome.
• Basic usage: It conveys profound regret over failing to prevent an accident or in a formal expression by the responsible person.

2. Common pitfalls and similar expressions

• Strong, formal regret
  • It is a formal expression of deep regret over a serious outcome, stronger than mild disappointment.