counterfoil
nounUK /ˈkaʊntəfɔɪl/
US /ˈkaʊntərfɔɪl/
A small piece of paper kept from a ticket or check to show what was written.
The clerk tore the ticket and kept the counterfoil for the records.
OTHER MEANINGS
2. The part of a check or receipt kept by the issuer as a record.
She filed the counterfoil of each check in the ledger.
3. A detachable section of a form retained after the main part is handed over.
The counterfoil on the form showed the reference number.
4. Anything that serves as a counterpart or check against another document.
The two halves of the contract acted as counterfoils to each other.