What does it mean to be a concubine in Nanjing dialect?

"concubine", a voucher used by merchants in Nanjing dialect, used to be made of bamboo chips, which should be called chips or bamboo chips. Sending a "concubine" is sending you a certificate. For example, the most common thing is that you go to a restaurant to buy a bowl of noodles. After paying, the cashier gives you a note that says what kind of noodles you bought, the quantity, and some stores have queue numbers. You should take this note to collect noodles; Some are just a queuing number, such as the queuing note received by the pager in the bank, the lottery number after paying the earnest money for buying a house, and so on. This voucher is only valid at the issuing merchant.