* Melted wax was used to seal letters or other documents that needed to be protected. When the wax cooled and hardened, the letter could not be opened without breaking the wax seal. The person who received the letter would see the unbroken seal and know that no one had opened it.
* A "signet" is a small object with letters or designs carved into it. A person could use it to mark a wax seal in order to show that he was the one who closed the seal.
* A "signet ring" is a ring with a signet on it.
* Something that is "unsealed" has not been sealed.