Online Etymology Dictionary

M: 13th letter, from Greek mu, from Semitic mem. The Roman symbol for 1,000; sometimes used in this sense in English 15c.-16c.; but in late 20c. newspaper headlines it stands for million. As a thickness of type, from 1680s.
M.A.S.H.: 1950, U.S. military acronym for Mobile Army Surgical Hospital.
M.D.: 1755, abbreviation of Latin Medicinæ Doctor "doctor of medicine."
M.E.: abbreviation of Middle English, attested by 1874.
M.F.N.: initialism (acronym) of most favored nation, attested from 1942.
M.P.: 1917, abbreviation of military police, which is recorded from 1827.
ma: 1823, childish or colloquial shortening of mamma.
ma'am: also maam, 1660s, colloquial shortening of madam (q.v.). At one time the ordinary respectful form of address to a married woman; later restricted to the queen and royal princesses or used by servants to their mistresses.
Maat: Egyptian goddess, literally (in Egyptian) "truth."
Mabel: fem. proper name, shortening of Amabel. Enjoyed its greatest popularity as a given name for girl babies in U.S. from c. 1884-1895.
Mac: casual, generic term of address for a man, 1928, from Irish and Gaelic mac, a common element in Scottish and Irish names (literally "son of;" see Mac-); hence used generally from early 19c. for "a Celtic Irishman."
Mac-: common element in Scottish and Irish names, from Old Celtic *makko-s "son." Cognate root *makwos "son" produced Old Welsh map, Welsh mab, ap "son;" also probably cognate with Old English mago "son, attendant, servant," Old Norse mögr "son," Gothic magus "boy, servant," Old English mægð "maid" (see maiden).
macabre (adj.): early 15c., originally in reference to a kind of morality show or allegorical representation of death and his victims, from Old French (danse) Macabré "(dance) of Death" (1376), of uncertain origin, probably a translation of Medieval Latin (Chorea) Machabæorum, literally "dance of the Maccabees" (leaders of the Jewish revolt against Syro-Hellenes; see Maccabees). The association with the dance of death seems to be from vivid descriptions of the martyrdom of the Maccabees in the Apocryphal books. The abstracted sense of "gruesome" is first attested 1842 in French, 1889 in English.
The typical form which the allegory takes is that of a series of pictures, sculptured or painted, in which Death appears, either as a dancing skeleton or as a shrunken corpse wrapped in grave-clothes to persons representing every age and condition of life, and leads them all in a dance to the grave. ["Encyclopaedia Britannica," 11th ed., 1911]
Macaca: monkey genus, Modern Latin, from Portuguese macaca, fem. of macaco, a name from an African language of the Congo.
macadam (n.): 1824, named for inventor, Scottish civil engineer John L. McAdam (1756-1836), who developed a method of leveling roads and paving them with gravel and outlined the process in his pamphlet "Remarks on the Present System of Road-Making" (1822). Originally the word meant road material consisting of a solid mass of stones of nearly uniform size laid down in layers (McAdam did not approve of the use of binding materials or rollers). The idea of mixing tar with the gravel began 1880s.
macadamia (n.): Australian evergreen tree, 1904, from Modern Latin (1858), named for Scotland-born chemist Dr. John Macadam (1827-1865), secretary of the Victoria Philosophical Institute, Australia, + abstract noun ending -ia.
macadamization (n.): 1826, noun of action from macadamize.
macadamize (v.): 1825 (implied in macadamized), from macadam + -ize. In early use also mcadamize. Related: Macadamizing. Also macadamise, macadamised.
macaque (n.): East Indian monkey, 1757, from French macaque, from Portuguese macaco "monkey," a Bantu word brought from Africa to Brazil (where it was applied 17c. to a type of monkey there). Introduced as a genus name 1840.
macaroni (n.): "tube-shaped food made of dried wheaten paste" [Klein], 1590s, from southern Italian dialectal maccaroni (Italian maccheroni), plural of maccarone, name for a kind of pasty food, possibly from maccare "bruise, batter, crush," which is of unknown origin, or from late Greek makaria "food made from barley."

Used by 1769 to mean "a fop, a dandy" ("typical of elegant young men" would be the sense in "Yankee Doodle") because it was an exotic dish at a time when certain young men who had traveled the continent were affecting French and Italian fashions and accents. There is said to have been a Macaroni Club in Britain, which was the immediate source of this usage in English.
macaronic (adj.): 1610s, in reference to a form of verse consisting of vernacular words in a Latin context with Latin endings; applied loosely to verse in which two or more languages are jumbled together; from Modern Latin macaronicus (coined 1517 by Teofilo Folengo), from dialectal Italian maccarone (see macaroni), in reference to the mixture of words in the verse: "quoddam pulmentum farina, caseo, botiro compaginatum, grossum, rude, et rusticanum" [Folengo].
macaroon (n.): 1610s, "small sweet cake consisting largely of ground almonds," from French macaron (16c.), from dialectal Italian maccarone, the name of a kind of pasty food (see macaroni). The French meaning is said to have been introduced 1552 by Rabelais. The -oon ending was conventional in 15c.-17c. English to add emphasis to borrowings of French nouns ending in stressed -on.
Macassar (adj.): especially in Macassar oil (1809), hair tonic originally advertised as made from materials obtained from Macassar (1660s), name of a district on the island of Celebes (modern Sulawesi); from native Mangkasara.
Macau: from Portuguese corruption of southern Chinese ama (name of a patron goddess of sailors) + ngao "bay, port."
macaw (n.): species of large, long-tailed birds, 1660s, from Portuguese macau, from a word in a Brazilian language, perhaps Tupi macavuana, which may be the name of a type of palm tree the fruit of which the birds eat.
Macbeth: masc. proper name, Gaelic, literally "son of life." The first reference to bad luck associated with Shakespeare's "Macbeth," and to avoidance of naming it, is from 1896, alludes to an incident of 1885, and says the tradition goes back "so far as modern memory can recall." The original superstition seems to have pertained particularly to the witches' scenes, which were played up dramatically in 19c. productions, and especially to Matthew Locke's 17c. music to accompany the witches' song, which was regularly played through the 19th century.
It is strange how the effect of this music has exerted such a long surviving influence on members of the dramatic profession. It is still considered most unlucky to sing, hum, or whistle the witch airs in the theatre except in the ways of business. [Young-Stewart, "The Three Witches," in "The Shakespearean," Sept. 15, 1896]

If you number an actor or actress among your friends, and desire to retain his or her friendship, there are three things you positively must not do, especially if the actor is of the old school. Do not whistle in the theatre, do not look over his shoulder into the glass while he is making up, and do not hum the witch's song from "Macbeth." ... [O]lder actors would almost prefer to lose their salary than go on in "Macbeth" on account of this song. They believe that it casts spells upon the members of the company. ["Some Odd Superstitions of the Stage," "Theatre" magazine, July 1909]
Maccabees: late 14c., from Late Latin Maccabæus, surname given to Judas, third son of Mattathias the Hasmonean, leader of the religious revolt against Antiochus IV, 175-166 B.C.E. Usually connected with Hebrew maqqabh "hammer," but Klein thinks it an inexact transliteration of Hebrew matzbi "general, commander of an army." Related: Maccabean.
Macduff: Gaelic Mac Dhuibh "son of Dubh," literally "black."
mace (n.1): "heavy metal weapon, often with a spiked head," late 13c., from Old French mace "a club, scepter" (Modern French masse), from Vulgar Latin *mattea (source also of Italian mazza, Spanish maza "mace"), from Latin mateola (in Late Latin also matteola) "a kind of mallet." The Latin word perhaps is cognate with Sanskrit matyam "harrow, club," Old Church Slavonic motyka "mattock," Old High German medela "plow" [Klein]. As a symbol of authority or office from mid-15c.
mace (n.2): "spice made from dry outer husk of nutmeg," late 14c., from Old French macis (in English taken as a plural and stripped of its -s), of uncertain origin, sometimes said to be a scribal error for Latin macir, the name of a red spicy bark from India, but OED finds this etymology unlikely.
Mace (n.3): chemical spray originally used in riot control, 1966, technically Chemical Mace, a proprietary name (General Ordnance Equipment Corp, Pittsburgh, Pa.), probably so called for its use as a weapon, in reference to mace (1). The verb is first attested 1968. Related: Maced; macing.
Macedonia: c. 1300, Macedone, from Latin Macedonius "Macedonian," from Greek Makedones "the Macedonians," literally "highlanders" or "the tall ones," related to makednos "long, tall," makros "long, large" (see macro-). French Macédoine "mixed cut fruit or vegetables" is early 19c., said to be a reference to the diversity of people in Alexander's empire.
Macedonian: c. 1300, from Latin Macedonius (see Macedonia) + -an.
macerate (v.): late 15c., a back-formation from maceration or else from Latin maceratus, past participle of macerare "soften, make soft, soak, steep," related to maceria "garden wall," originally "of kneaded clay," from PIE *mak-ero-, suffixed form of root *mag- "to knead" (source also of Greek magis "kneaded mass, cake," mageus "one who kneads, baker;" Old Church Slavonic mazo "to anoint, smear;" Breton meza "to knead;" Middle Irish maistir "to churn"), also "to fashion, fit" (compare make (v.)). Related: Macerated; macerating.
maceration (n.): late 15c., from Latin macerationem (nominative maceratio), noun of action from past participle stem of macerare (see macerate).
Mach: measure of speed relative to the speed of sound (technically Mach number), 1937, named in honor of Austrian physicist Ernst Mach (1838-1916).
machete (n.): 1590s (in pseudo-Spanish form macheto), from Spanish machete, probably a diminutive of macho "sledge hammer," alteration of mazo "club," which is probably [Barnhart] a dialectal variant of maza "mallet," from Vulgar Latin *mattea "war club" (see mace (n.1)). An alternative explanation traces macho to Latin marculus "a small hammer," diminutive of marcus "hammer," from a base parallel to that of Latin malleus (see mallet).
Machiavelli: see Machiavellian. His name was Englished 16c.-18c. as Machiavel.
Machiavellian (adj.): "cunning, deceitful, unscrupulous," 1570s, from Niccolo Machiavelli (1469-1527), Florentine statesman and author of "Il Principe," a work advising rulers to place advantage above morality. A word of abuse in English well before his works were translated ("The Discourses" 1636, "The Prince" 1640), in part because his books were Indexed by the Church, in part because of French attacks on him (such as Gentillet's, translated into English 1602).
machinable (adj.): 1896, from machine (v.) + -able. Related: Machinability.
machinate (v.): "lay plots, intrigue," c. 1600, a back-formation from machination, or else from Latin machinatus, past participle of machinari (see machination). Related: Machinated; machinating; machinator.
machination (n.): late 15c., "a plotting, intrigue," from Old French machinacion "plot, conspiracy, scheming, intrigue," from Latin machinationem (nominative machinatio) "device, contrivance, machination," noun of action from past participle stem of machinari "contrive skillfully, to design; to scheme, to plot," from machina (see machine (n.)). Related: Machinations.
machinator (n.): 1610s, from Latin machinator, agent noun from past participle stem of machinari "design, contrive, plot" (see machine (n.)).
machine (n.): 1540s, "structure of any kind," from Middle French machine "device, contrivance," from Latin machina "machine, engine, military machine; device, trick; instrument" (source also of Spanish maquina, Italian macchina), from Greek makhana, Doric variant of mekhane "device, means," related to mekhos "means, expedient, contrivance," from PIE *maghana- "that which enables," from root *magh- (1) "to be able, have power" (source also of Old Church Slavonic mogo "be able," Old English mæg "I can;" see may (v.)).

Main modern sense of "device made of moving parts for applying mechanical power" (1670s) probably grew out of mid-17c. senses of "apparatus, appliance" and "military siege-tower." In late 19c. slang the word was used for both "penis" and "vagina," one of the few so honored. Political sense is U.S. slang, first recorded 1876. Machine age is attested by 1851:
The idea of remodelling society at public meetings is one of the least reasonable which ever entered the mind of an agitator: and the notion that the relations of the sexes can be re-arranged and finally disposed of by preamble and resolution, is one of the latest, as it should have been the last, vagary of a machine age. ["The Literary World," Nov. 1, 1851]
Machine for living (in) "house" translates Le Corbusier's machine à habiter (1923).
machine (v.): mid-15c., "decide, resolve," from Old French and Latin usages (see machine (n.)). Related: Machined; machining. Meaning "to make or form on a machine" is from 1878. Related: Machined; machining.
machine-gun (n.): 1870, from machine (n.) + gun (n.). As a verb from 1915. Related: Machine-gunned; machine-gunning.
machinery (n.): 1680s; from machine (n.) + -ery. Originally theatrical, "devices for creating stage effects" (which also was a sense of Greek mekhane); meaning "machines collectively" is attested from 1731. Middle English had machinament "a contrivance" (early 15c.).
machinist (n.): 1706, "engineer, mechanical inventor," a hybrid from machine (n.) + -ist. Meaning "machine operator" is attested from 1879.
machismo (n.): 1940, from American Spanish machismo, from Spanish macho "male" (see macho) + ismo (see -ism).
macho: 1928 (n.) "tough guy," from Spanish macho "male animal," noun use of adjective meaning "masculine, virile," from Latin masculus (see masculine). As an adjective, first attested in English 1959.