密封

1. Origins, structure, and basic meaning

• Structure: Written 密封 and read みっぷう, it means sealing something tightly against air, moisture, or leakage.
• Basic usage: It is used for preserving food containers and enclosing samples.

2. Common pitfalls and similar expressions

• Stronger than putting on a lid
  • Airtight integrity is intended, not merely visual closure.