Mortgage

A loan in which the borrower puts up the title to real estate as security (collateral) for a loan.
If the borrower doesn't pay back the debt on time, the lender can foreclose on the real estate and have it sold to pay off the loan.
A loan used to finance the purchase of real estate, generally with specified payment periods and interest rates.

A mortgage is the transfer of an interest in property (or the equivalent in law - a charge) to a lender as a security for a debt - usually a loan of money. While a mortgage in itself is not a debt, it is the lender's security for a debt.

It is a transfer of an interest in land (or the equivalent) from the owner to the mortgage lender, on the condition that this interest will be returned to the owner when the terms of the mortgage have been satisfied or performed.

In other words, the mortgage is a security for the loan that the lender makes to the borrower.