From Longman Dictionary of Contemporary Englishcounterfoilcoun‧ter‧foil /ˈkaʊntəfɔɪl $ -tər-/ noun [countable] BBthe part of something such as a cheque that you keep as a record
Examples from the Corpus
counterfoil• Please collect counterfoils and money from your class members and send to Joan Daniels as soon as possible.• The numbered counterfoil of each certificate was returned to the kachcheri by the headman.• Both the counterfoil and the voting slip have identical numbers printed on them similar to a cloakroom or raffle tickets.• It was not easy to store the counterfoils of sale vouchers out of the range of white ants.• If you paid by postal order, take the counterfoils to the post office for a refund.• Please complete the back of the ticket counterfoil and send to the Amnesty Fundraising Department, with your request for extra tickets.• I enclose the one-way ticket counterfoil as proof of purchase, and look forward to hearing from you.• Is the practice of marking each voting counterfoil with the electors electoral role number to continue in the forthcoming election?From Longman Business Dictionarycounterfoilcoun‧ter‧foil /ˈkaʊntəfɔɪl-tər-/ noun [countable] British EnglishBANKING the part of something such as a cheque that you complete and keep as a record of how much you have spentSYNCHEQUE STUBI enclose the ticket counterfoil as proof of purchase.Origin counterfoil (1700-1800) counter- + foil “piece of paper, counterfoil” ((15-18 centuries)) (from Old French; → FOIL1) 