The origins of the word mortgage come from the French words mort (death), and gage (a pledge).

The word mortgage came into Middle English by way of Middle and Old French. For a greater portion of the Middle English period French was the language of the ruling elite, many of which spoke little if any English.

Taking out a mortgage did not mean that the mortgagee (borrower) expected to be killed if he did not pay back the mortgage; it merely meant that he would lose the mortgaged property if he fell behind on his payments. It had to do with the doubtfulness of whether or not the mortgagor will pay the debt.