Three-letter voucher (3)
I believe the answer is:
iou
(Other definitions for iou that I've seen before include "I owe you" , "Admission of liability" , "Promissory note" , "Debtor's note" , "Promise to pay in vowels" .)
I believe the answer is:
iou
(Other definitions for iou that I've seen before include "I owe you" , "Admission of liability" , "Promissory note" , "Debtor's note" , "Promise to pay in vowels" .)