Online Etymology Dictionary

machree: Irish expression, 1829, from Irish-Gaelic mo chroidhe "(of) my heart," hence "my dear!"
Machu Picchu: from Quechua (Inca) machu "old man" + pikchu "peak."
Mack: proprietary name for a brand of heavy automobile trucks, named for brothers John M., Augustus F., and William C. Mack, who established Mack Brothers Company, N.Y., N.Y., in 1902. Their trucks formally known as "Mack Trucks" from 1910.
Mackenzie: river in Canada, named for Scottish fur trader and explorer Sir Alexander Mackenzie (1764-1820) who discovered and explored it 1789.
mackerel (n.): edible fish, c. 1300, from Old French maquerel "mackerel" (Modern French maquereau), of unknown origin but apparently identical with Old French maquerel "pimp, procurer, broker, agent, intermediary," a word from a Germanic source (compare Middle Dutch makelaer "broker," from Old Frisian mek "marriage," from maken "to make"). The connection is obscure, but medieval people had imaginative notions about the erotic habits of beasts. The fish approach the shore in shoals in summertime to spawn. Exclamation holy mackerel is attested from 1876.
Mackinaw: type of boat used on the Great Lakes, 1812, from Mackinac, name of a port and island in Michigan, from Ojibway (Algonquian) mitchimakinak "many turtles," from mishiin- "be many" + mikinaak "snapping turtle." As a type of heavy blanket given to the Indians by the U.S. government, it is attested from 1822.
mackintosh (n.): waterproof outer coat, 1836, named for Charles Macintosh (1766-1843), inventor of a waterproofing process (patent #4804, June 17, 1823). The surname is from Gaelic Mac an toisich "Son of the chieftain."
macrame (n.): 1869, from French macramé, from Turkish maqrama "towel, napkin," from Arabic miqramah "embroidered veil."
macro (n.): 1959 in computing sense, shortened from macro-instruction.
macro-: word-forming element meaning "long, abnormally large, on a large scale," taken into English via Middle French and Medieval Latin from Greek makros "long, large," from PIE root *mak- "long, thin" (source also of Latin macer "lean, thin;" Old Norse magr, Old English mæger "lean, thin;" Greek mekos "length").
macrobiotic (adj.): also macro-biotic, "inclined to prolong life," 1797, from Greek makrobiotikos "long-lived," from makros "long" (see macro-) + bios "life" (see bio-). The specific reference to a Zen Buddhist dietary system dates from 1936.
macrocephalic (adj.): 1851, from Greek makrokephalos; see macro-. Second element is from Greek kephale "head" (see cephalo-). Related: Macrocephalous; macrocephaly.
macrocosm (n.): c. 1600, "the great world" (the universe, as distinct from the "little world" of man), from Old French macrocosme (c. 1300) and directly from Medieval Latin macrocosmus, from Greek makros "large, long" (see macro-) + kosmos (see cosmos).
macroeconomic (adj.): also macro-economic, 1938, from macro- + economic.
macroeconomics (n.): also macro-economics, 1948, from macroeconomic; also see -ics.
macroinstruction (n.): also macro-instruction, 1959, from macro- + instruction.
macromolecule: 1886, from macro- + molecule. Apparently coined in "On Macro-molecules, with the Determinations of the Form of Some of Them," by Anglo-Irish physicist G. Johnstone Stoney (1826–1911). Originally of crystals. Meaning "molecule composed of many atoms" is from 1935, from German makromolekul (1922). Related: Macromolecular.
macron (n.): "short horizontal line placed over a vowel to indicate length," 1827, from Greek makron, neuter of makros "long" (see macro-).
macropaedia (n.): 1974, introduced with the 15th edition of the "Encyclopaedia Britannica," from macro- + ending from encyclopaedia.
macrophage (n.): 1890, from macro- + -phage.
macrophotography (n.): 1863, from macro- + photography.
macroscopic (adj.): 1872, from macro- + ending from microscopic. Related: Macroscopical; macroscopically.
macrospore (n.): 1859, from macro- + spore (n.).
macula (n.): plural maculae, from Latin macula "spot, stain," used of various spots (sunspots, markings on minerals, etc.), from Proto-Italic *smalto-, of uncertain origin. Especially the macula lutea in the eye.
macular (adj.): 1822, from macula + -ar.
maculate (adj.): "spotted," late 15c., from Latin maculatus, past participle of maculare "to make spotted, to speckle," from macula "spot, stain" (see macula). Middle English also had maculation "sexual defilement, sinning" (late 15c.).
maculate (v.): early 15c., from Latin maculatus, past participle of maculare "to make spotted, to speckle," from macula "spot, stain" (see macula). Related: Maculated; maculating.
maculation (n.): mid-15c., from Latin maculationem (nominative maculatio), noun of action from past participle stem of maculare (see maculate).
macule (n.): "blemish, spot," late 15c., from Latin macula (see macula), perhaps via French macule.
mad (adj.): late 13c., from Old English gemædde (plural) "out of one's mind" (usually implying also violent excitement), also "foolish, extremely stupid," earlier gemæded "rendered insane," past participle of a lost verb *gemædan "to make insane or foolish," from Proto-Germanic *ga-maid-jan, demonstrative form of *ga-maid-az "changed (for the worse), abnormal" (source also of Old Saxon gimed "foolish," Old High German gimeit "foolish, vain, boastful," Gothic gamaiþs "crippled, wounded," Old Norse meiða "to hurt, maim"), from intensive prefix *ga- + PIE *moito-, past participle of root *mei- (1) "to change" (source also of Latin mutare "to change," mutuus "done in exchange," migrare "to change one's place of residence;" see mutable).

Emerged in Middle English to replace the more usual Old English word, wod (see wood (adj.)). Sense of "beside oneself with excitement or enthusiasm" is from early 14c. Meaning "beside oneself with anger" is attested from early 14c., but deplored by Rev. John Witherspoon (1781) as an Americanism. It now competes in American English with angry for this sense. Of animals, "affected with rabies," from late 13c. Phrase mad as a March hare is attested from 1520s, via notion of breeding season; mad as a hatter is from 1829 as "demented," 1837 as "enraged," according to a modern theory supposedly from erratic behavior caused by prolonged exposure to poison mercuric nitrate, used in making felt hats. For mad as a wet hen see hen. Mad money is attested from 1922; mad scientist is from 1891.
mad (adv.): late 14c., from mad (adj.).
Madagascar: large island off the east coast of Africa, from Mogadishu, the name of the city in Somalia, due to an error by Marco Polo in reading Arabic, whereby he thought the name was that of the island. There is no indigenous name for the whole island. Related: Madagascan.
madam: c. 1300, from Old French ma dame, literally "my lady," from Latin mea domina (compare madonna). Meaning "female owner or manager of a brothel" is first attested 1871.
madame: 1590s, see madam, which is an earlier borrowing of the same French phrase. Originally a title of respect for a woman of rank, now given to any married woman. OED recommends madam as an English title, madame in reference to foreign women.
madarosis (n.): "loss of the eyelashes," 1690s, medical Latin, from Greek madarosis "baldness." Related: Madarotic.
madcap: 1580s, noun and adjective, from mad (adj.) + cap, used here figuratively for "head." Related: Madcappery.
madden (v.): "to drive to distraction," 1822; earlier "to be mad" (1735), from mad (adj.) + -en (1). Related: Maddened; maddening. The earlier verb was simply mad (early 14c., intransitive; late 14c., transitive), from the adjective.
maddening (adj.): 1743, from present participle of madden. Related: Maddeningly.
madder (n.): type of plant (in modern use Rubia tinctorum) used for making dyes, Old English mædere, from PIE *modhro- "dye plant" (source also of Old Norse maðra, Old High German matara "madder," Polish modry, Czech modry "blue").
madding (adj.): present participle adjective from obsolete verb mad "to make insane; to become insane" (see madden); now principally in the phrase far from the madding crowd, title of a novel by Hardy (1874), who lifted it from a line of Gray's "Elegy" (1749), which seems to echo a line from Drummond of Hawthornden from 1614 ("Farre from the madding Worldling's hoarse discords").
maddish (adj.): 1570s, from mad (adj.) + -ish.
made (adj.): late 14c., from Middle English maked, from Old English macod "made," past participle of macian "to make" (see make). Made up "invented" is from 1789; of minds, "settled, decided," from 1873. To be a made man is in Marlowe's "Faust" (1590). To have it made (1955) is American English colloquial. Grose's dictionary of slang and cant (1785) has for this word what might be the shortest and most cynical definition ever penned: "MADE. Stolen. Cant."
Madeira (n.): white wine, 1540s, from island of Madeira in the Atlantic, from Portuguese madeira "wood," because the island formerly was thickly wooded, from Latin materia "wood, matter" (see matter (n.)).
Madeleine: fem. proper name, variation of Madeline. The kind of small, rich confection is attested from 1845, said in OED to be named for Madeleine Paulmier, 19c. French pastry cook; any use with a sense of "small thing that evokes powerful nostalgia" is due to Proust (1922).
Madeline: fem. proper name, from French Magdalene (q.v.). Compare also Madeleine.
mademoiselle: mid-15c., "unmarried Frenchwoman," from French mademoiselle (12c.), from a compound of ma dameisele (see damsel), literally "young mistress."
Madge: pet form of fem. proper name Margaret.
MADGE. The private parts of a woman. [Grose, "Dictionary of the Vulgar Tongue," London, 1785]
madhouse (n.): 1680s, from mad + house (n.). Figurative use by 1919.
Madison: surname attested from early 15c., probably in many cases a variant of Mathieson "son of Matthew," but in some cases perhaps "son of Maddy," from the pet form of the fem. proper name Maud. The city in Wisconsin, U.S., was named 1836 for U.S. President James Madison, who had died that year. As the name of a popular dance of 1960, its signification is unknown; supposedly it originated in Baltimore.
Madison Avenue: "values and business of advertising and public relations," 1954, from the street in Manhattan, laid out c. 1836 and named for U.S. President James Madison. The concentration of advertising agencies there seems to date from the 1940s.