誓約

1. Origins, structure, and basic meaning

• Structure: 誓約 is read せいやく and means a firm pledge to uphold something.
• Basic usage: It is used for pledging to follow rules upon joining a group or discussing a breach of that pledge.

2. Common pitfalls and similar expressions

• More solemn than 約束
  • 約束 is widely used for everyday promises, while 誓約 is formal and conveys firm commitment and responsibility. 誓約を交わした means entering into a pledge.