noun
stamp
STAMP/stæmp/
A small adhesive label showing postage has been paid.
A stamp is affixed to the envelope.

Etymology
An official imprint came to name the small label proving postage had been marked as paid.
More examples
- The letter needs another stamp.
- He collects stamps from different countries.
Forms
stamp · stamps
Similar words
- postage
- The charge for carrying mail rather than the label.
- postmark
- A cancellation mark applied by the postal service.