Having recently applied for a mortgage, I decided to look into this curious-sounding word. Since I took French in high school, I know that “mort” means dead, as used in the English words “mortician” and “mortify.” I also suspected that “gage” meant deed, but I assumed it meant so only in French. The fact is, “gage” is also an English word meaning something deposited as security (I can’t recall ever seeing this word in use before). So a “mortgage” is a dead deed or security, so called because if you don’t pay it, the pledged property is “dead” to you. If you do pay it, it is “dead” to the holder of the pledge.