Pronounced kǎ nú, this term literally means a "slave of cards." Because of the popular use of credit cards in large Chinese cities, some people – especially youngsters with shopping addictions and small salaries – gradually become credit card slaves, who sometimes borrow from one credit card to pay off another credit card.
Let's put it into context:
Allen: Hey, Phil, where are you going?
Phil: To the bank, to apply for a credit card.
Allen: Really? But I thought you already had three or four credit cards. Why another one?
Phil: Well, I am a little in debt to the banks, so I need another one to make a payment.
Allen: You are really a kǎ nú.
