superscribe

Verb

• write on the top or outside
  • "superscribe one's name and address"
• write on the outside or upper part of
  • "superscribe an envelope"
• to write on the exterior of, the surface of, or above.
• to write (something) on the exterior of an object, such as a document or an envelope.
• To address (an envelope etc.).

Examples

• "His wife superscribed her own notes on each of his letters before sending them in packets to the editor."