開封

1. Origins, structure, and basic meaning

• Structure: The spelling is 開封, read かいふう, and it combines 開, meaning open, with 封, meaning seal.
• Basic usage: The basic sense of 開封 is opening a sealed or closed envelope, box, package, or similar item.

2. Common pitfalls and similar expressions

• Breaking the seal rather than using the contents
  • Both examples use the form 開封. The focus is on the initial act of opening sealed packaging, not the entire process of removing or using what is inside.
• A delivered box and a recipient-only envelope
  • 届いた箱を開封する前に宛名を確認した。 — I checked the addressee before opening the delivered box.
  • この封筒は本人が開封してください。 — Only the intended recipient should open this envelope.