signet
nounUK /ˈsɪɡnət/
US /ˈsɪɡnət/
A signet is a small ring or stamp with a special mark used to seal letters.
The king pressed his signet into the warm wax to close the letter.
OTHER MEANINGS
2. A small seal, especially one set in a ring, used to give official approval to documents.
The clerk checked the signet on the parchment before filing it.
3. A mark or impression made by such a seal.
The signet in the wax proved the message was genuine.
4. A signet ring worn as a symbol of authority or family identity.
He wore his grandfather's signet on his little finger.