late 14c., morgage, "a conveyance of property on condition 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- was restored in Modern English based on Latin.
And it seemeth, that the cause why it is called mortgage is, for that it is doubtful whether the feoffor will pay at the day limited such sum or not: and if he doth not pay, then the land which is put in pledge upon condition for the payment of the money, is taken from him for ever, and so dead to him upon condition, &c. And if he doth pay the money, then the pledge is dead as to the tenant, &c. [Coke upon Littleton, 1664]
"to grant (immovable property) as security for money lent or contracted to be paid," late 15c., morgagen, from mortgage (n.). Related: Mortgaged; mortgaging.
"one who grants a property as security for debt," 1580s, agent noun in Latin form from mortgage (v.). Native form mortgager is attested from 1630s. Barbarous mortgageor seems to be limited to legal writing.
Proto-Indo-European root meaning "to rub away, harm." Possibly identical with the root *mer- that means "to die" and forms words referring to death and to beings subject to death.
It forms all or part of: amaranth; ambrosia; amortize; Amritsar; immortal; manticore; marasmus; mare (n.3) "night-goblin, incubus;" morbid; mordacious; mordant; moribund; morsel; mort (n.2) "note sounded on a horn at the death of the quarry;" mortal; mortality; mortar; mortgage; mortify; mortmain; mortuary; murder; murrain; nightmare; post-mortem; remorse.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit mrnati "crushes, bruises," mriyate "to kill," martave "to die," mrta- "died, dead," mrtih "death," martah "mortal man," amrta- "immortal;" Avestan miriia- "to die," miryeite "dies," Old Persian martiya- "man;" Hittite mer- "to disappear, vanish," marnu- "to make disappear;" Armenian meranim "to die;" Greek marainein "to consume, exhaust, put out, quench," marasmus "consumption," emorten "died," brotos "mortal" (hence ambrotos "immortal"); Latin mors (genitive mortis) "death," mori "to die;" Armenian merani- "to die;" Gothic maurþr, Old English morþ "murder;" Old Irish marb, Welsh marw "dead;" Lithuanian mirti "to die," mirtis "death;" Old Church Slavonic mreti "to die," mrutvu "dead;" Russian mertvyj, Serbo-Croatian mrtav "dead."
1680s, "pledge (something) without giving up control of it; pawn; mortgage," from hypothecat-, past-participle stem of Medieval Latin hypothecare, from Late Latin hypotheca "a pledge," from Greek hypothēkē "a deposit, pledge, mortgage," from hypo- "beneath, under" (see hypo-) + tithenai "to put, to place," from reduplicated form of PIE root *dhe- "to set, put." Related: Hypothecated; hypothecating; hypothecation; hypothecary.
c. 1400, pleggen, "to promise" (something to someone), "to give (something) over as security for repayment," also "promise faith to," from pledge (n.) and from Old French plegier, from plege (n.). From mid-15c. as "to stand surety for, be responsible for;" late 15c. as "to mortgage." The transitive meaning "put (someone) under oath" is from 1570s; sense of "to solemnly promise or guarantee" is from 1590s, as is the sense of "to drink a toast." Related: Pledged; pledging.