Definition: The word "assume mortgage" refers to a situation where someone assumes the financial responsibility for another person's debt or loan, without their own consent. In this context, "assumption" means that the creditor is assuming the right to collect on the borrower's debts from the other party. Assuming the mortgaged property can be sold for a profit if the mortgage is paid off and transferred to a new owner, or in exchange for the payment of additional fees. The term was popularized by the 2015 movie "Taxi Driver," where Paul Newman plays an undercover cop who assumes the identity of another taxi driver and commits crimes for the benefit of his client.