late 12c., "God's forgiveness of his creatures' offenses," from Old French mercit, merci (9c.) "reward, gift; kindness, grace, pity," from Latin mercedem (nominative merces) "reward, wages, pay, hire" (in Vulgar Latin "favor, pity;" in Medieval Latin "thanks; grace"), from merx (genitive mercis) "wares, merchandise" (see market (n.)). In Church Latin (6c.) it was given a specific application to the heavenly reward earned by those who show kindness to the helpless and those from whom no requital can be expected.
Meaning "disposition to forgive or show compassion" is attested from early 13c. Sense of "an act or exercise of forbearance or good will" is from c. 1300. As an interjection, attested from mid-13c. (short for may God have mercy, have mercy on me, etc.). Many of the English senses are found earlier in French, but in French the word largely has been superseded by miséricorde except as a word of thanks. Sense of "discretionary action" (as in at (one's) mercy) is from mid-14c. Seat of mercy "golden covering of the Ark of the Covenant" (1530), hence "the throne of God," is Tyndale's loan-translation of Luther's gnadenstuhl, an inexact translation of Latin propitiatorium, ultimately a rendering of Hebrew kapporeth, literally "propitiatory."
fem. proper name, from Spanish, abbreviation of Maria de las Mercedes "Mary of the Mercies," from plural of merced "mercy, grace," from Latin mercedem (nominative merces) "hire, pay, wage, salary; rent, income; a price for anything;" see mercy. The early Christians gave a spiritual meaning to the purely financial classical senses of the Latin word, which also, in its original senses, entered Middle English as mercede "wages" (late 14c.).
"punishment by arbitrary or discretionary fine," 1215, earlier amercy, Anglo-French amercier "to fine," from merci "mercy, grace" (see mercy). The legal phrase estre a merci "to be at the mercy of" (a tribunal, etc.) was corrupted to estre amercié in an example of how an adverbial phrase in legalese can become a verb (compare abandon).
Frans hom ne seit amerciez pour petit forfet. [Magna Charta]
Related: Amercement; amerciable/amerceable.
New York City's Gramercy Park is named for the Gramercy Farm which once stood there; the first part of the name is an 18c. folk-etymology from Crommeshie Fly, the name of a former marsh or shallow pond that stood nearby, itself a mangling of New Netherlands Dutch Crommessie Vly, the first part of which represents either *Krom Moerasje "little crooked swamp" or *Krom Messje "little crooked knife," said to have been the name of a brook flowing into (or out of) the pond.
c. 1200, "recitation of the 51st Psalm" (in Vulgate, the 50th), one of the "Penitential Psalms," so called from the phrase Miserere mei Deus "Have mercy upon me, O God," the opening line of it in the Vulgate, from Latin miserere "feel pity, have compassion, commiserate," second person singular imperative of misereri "to have mercy," from miser "wretched, pitiable" (see miser).
From 15c.-17c. it was used as an informal measure of time, "the time it takes to recite the Miserere." The musical settings of the psalm are noted for their striking effectiveness. The Latin verb also is in miserere mei "kind of severe colic ('iliac passion') accompanied by excruciating cramps and vomiting of excrement" (1610s); literally "have mercy on me."