late 14c., from Old French morgage, literally "dead pledge," from mort "dead" + gage "pledge." So called because the deal dies when the debt is paid or when payment fails.
late 14c., morgage, "conveyance of property as security for a loan or agreement," from Old French morgage (13c.), mort gaige, literally "dead pledge" (replaced in modern French by hypothèque), from mort "dead" (see mortal (adj.)) + gage "pledge" (see wage (n.)). So called because the deal dies either when the debt is paid or when payment fails. Old French mort is from Vulgar Latin *mortus "dead," from Latin mortuus, past participle of mori "to die" (from PIE root *mer- "to rub away, harm," also "to die" and forming words referring to death and to beings subject to death). The -t- restored in English based on Latin.