Definition: The word "refinance mortgage rates" refers to a process in which a borrower refits their existing mortgage loan with another loan at a lower interest rate. This can be done either through a traditional home equity loan, where the lender takes a portion of your home's value as collateral and refinances it for a new loan, or by using an adjustable-rate mortgage (ARM). The process involves changing the terms of the original loan to match those of the refi, such as lowering the interest rate or changing the payment schedule.