A person with a loan (or mortgage), who hasn't been able to pay the instalments on time. In such case
the bank may or may not change the
conditions of the repayment to slightly more favourable ones. Because the borrower might not be able to pay back the loan, the loan contract is
half dead. Like a zombie.
Bank
employee 1: I don't get you, is this a risky loan, or is the guy paying the instalments on time?
Bank
employee 2: He has barely paid any instalment on time, he is a proper zombie
borrower.