Online Etymology Dictionary

mottle (v.): 1670s; see mottle (n.). Related: Mottled; mottling.
mottled (adj.): 1670s, past participle adjective; see mottle (v.).
motto (n.): 1580s, from Italian motto "a saying, legend attached to a heraldic design," from Late Latin muttum "grunt, word," from Latin muttire "to mutter, mumble, murmur" (see mutter).
moue (n.): "pout," 1850, from French moue "mouth, lip, pout," from Old French moe, perhaps from Middle Dutch mouwe, with the same senses, but this could as easily be from French. As a verb from 1909.
mould: chiefly British English spelling of mold in various senses. Related: Moulded; moulding.
moulder: see molder. Related: Mouldered; mouldering.
mouldy (adj.): see moldy.
moult: see molt.
mound (n.): 1550s, "hedge, fence," also "embankment, dam" (a sense probably influenced by mount (n.)). The relationship between the noun and the verb is uncertain. Commonly supposed to be from Old English mund "hand, protection, guardianship" (cognate with Latin manus), but this is not certain (OED discounts it on grounds of sense). Perhaps a confusion of the native word and Middle Dutch mond "protection," used in military sense for fortifications of various types, including earthworks. From 1726 as "artificial elevation" (as over a grave); 1810 as "natural low elevation." As the place where the pitcher stands on a baseball field, from 1912.
mound (v.): 1510s, "to enclose with a fence;" c. 1600 as "to enclose with an embankment;" see mound (n.). From 1859 as "to heap up." Related: Mounded; mounding.
mount (v.): c. 1300, "to mount a horse;" mid-14c., "to rise up, ascend; fly," from Old French monter "to go up, ascend, climb, mount," from Vulgar Latin *montare, from Latin mons (genitive montis) "mountain" (see mount (n.1)). Meaning "to set or place in position" first recorded 1530s. Sense of "to get up on for purposes of copulation" is from 1590s. Related: Mounted; mounting.
mount (n.1): "hill, mountain," mid-13c., from Anglo-French mount, Old French mont "mountain;" also perhaps partly from Old English munt "mountain;" both the Old English and the French words from Latin montem (nominative mons) "mountain," from PIE root *men- (2) "to stand out, project" (source also of Latin eminere "to stand out;" Sanskrit manya "nape of the neck," Latin monile "necklace;" Old Irish muin "neck," Welsh mwnwgl "neck," mwng "mane;" Welsh mynydd "mountain").
mount (n.2): "that on which something is mounted," 1739, from mount (v.). The colloquial meaning "a horse for riding" is first recorded 1856.
mountain (n.): c. 1200, from Old French montaigne (Modern French montagne), from Vulgar Latin *montanea "mountain, mountain region," noun use of fem. of *montaneus "of a mountain, mountainous," from Latin montanus "mountainous, of mountains," from mons (genitive montis) "mountain" (see mount (n.1)).

Until 18c., applied to a fairly low elevation if it was prominent (such as Sussex Downs, the hills around Paris). As an adjective from late 14c. Mountain dew "raw and inferior whiskey" first recorded 1839; earlier a type of Scotch whiskey (1816); Jamieson's 1825 "Supplement" to his Scottish dictionary defines it specifically as "A cant term for Highland whisky that has paid no duty." Mountain-climber recorded from 1839; mountain-climbing from 1836.
mountaineer (n.): c. 1600, "dweller in mountains," from mountain + -eer. Verb meaning "to be a mountain-climber" is from 1803.
mountainous (adj.): late 14c., from Old French montagneux, from Vulgar Latin *montaneosus "mountainous," from *montanea (see mountain).
mountebank (n.): "a doctor that mounts a bench in the market, and boasts his infallible remedies and cures" [Johnson], 1570s, from Italian montambanco, contraction of monta in banco "quack, juggler," literally "mount on bench" (to be seen by crowd), from monta, imperative of montare "to mount" (see mount (v.)) + banco, variant of banca "bench" (see bank (n.2)). Figurative and extended senses from 1580s.
mounted (adj.): 1580s, "on horseback," past participle adjective from mount (v.). From 1854 as "set up for display."
Mountie (n.): 1914, member of the Royal Canadian (originally North-west) Mounted Police, formed 1873 to keep order in the former Hudson's Bay Company lands. Also see -ie.
mourn (v.): Old English murnan "to mourn, bemoan, long after," also "be anxious about, be careful" (class III strong verb; past tense mearn, past participle murnen), from Proto-Germanic *murnan "to remember sorrowfully" (source also of Old Saxon mornon, Old High German mornen, Gothic maurnan "to mourn," Old Norse morna "to pine away"), probably from PIE root *(s)mer- "to remember" (see memory); or, if the Old Norse sense is the base one, from *mer- "to die, wither." Related: Mourned; mourning.
mourner (n.): late 14c., agent noun from mourn (v.).
mournful (adj.): early 15c., from mourn + -ful. Related: Mournfully; mournfulness.
mourning (n.): Old English murnung "complaint, grief," verbal noun from mourn (v.).
mouse (n.): Old English mus "small rodent," also "muscle of the arm," from Proto-Germanic *mus (source also of Old Norse, Old Frisian, Middle Dutch, Danish, Swedish mus, Dutch muis, German Maus "mouse"), from PIE *mus- (source also of Sanskrit mus "mouse, rat," Old Persian mush "mouse," Old Church Slavonic mysu, Latin mus, Lithuanian muse "mouse," Greek mys "mouse, muscle").

Plural form mice (Old English mys) shows effects of i-mutation. Contrasted with man (n.) from 1620s. Meaning "black eye" (or other discolored lump) is from 1842. Computer sense is from 1965, though applied to other things resembling a mouse in shape since 1750, mainly nautical.
Parturient montes, nascetur ridiculus mus [Horace]
mouse (v.): "to hunt mice," mid-13c., from mouse (n.). Related: Moused; mousing.
mouse-hole (n.): early 15c., from mouse (n.) + hole (n.).
mouser (n.): "cat that hunts mice," c. 1400, agent noun from mouse (v.).
mousetrap (n.): late 15c., from mouse (n.) + trap (n.). Figurative use from 1570s. The thing is older than the word. Old English had musfealle; Middle English had mouscacche (late 14c.).
mousse (n.): 1892, in cookery sense, from French mousse, from Old French mousse "froth, scum," from Late Latin mulsa "mead," from Latin mulsum "honey wine, mead," from neuter of mulsus "mixed with honey," related to mel "honey" (see Melissa). Meaning "preparation for hair" is from 1977. As a verb in this sense from 1984.
moustache (n.): see mustache. Related: moustachial.
mousy (adj.): 1812 with reference to quietness; 1853, of color; from mouse + -y (2).
mouth (n.): Old English muþ "mouth, opening, door, gate," from Proto-Germanic *munthaz (source also of Old Saxon, Old Frisian muth, Old Norse munnr, Danish mund, Middle Dutch mont, Dutch mond, Old High German mund, German Mund, Gothic munþs "mouth"), with characteristic loss of nasal consonant in Old English (compare tooth, goose), from PIE *mnto-s (source also of Latin mentum "chin"). In the sense of "outfall of a river" it is attested from late Old English; as the opening of anything with capacity (a bottle, cave, etc.) it is recorded from c. 1200. Mouth-organ attested from 1660s.
mouth (v.): c. 1300, "to speak," from mouth (n.). Related: Mouthed; mouthing. Old English had muðettan "to blab."
mouth-watering (adj.): 1822, from mouth (n.) + water (v.).
mouthful (n.): 1520s, "as much as a mouth can hold," from mouth (n.) + -ful. Meaning "a lot to say" is from 1748.
mouthpiece (n.): also mouth-piece, 1680s, "casting fitted on an open end of a pipe, etc.," from mouth (n.) + piece (n.). Meaning "piece of a musical instrument that goes in the mouth" is from 1776. Sense of "one who speaks on behalf of others" is from 1805; in the specific sense of "lawyer" it is first found 1857.
mouthwash (n.): also mouth-wash, 1840, from mouth (n.) + wash (n.).
mouthy (adj.): 1580s, from mouth (n.) + -y (2).
mouton enrage (n.): 1932, from French mouton enragé, literally "angry sheep." "A normally calm person who has become suddenly enraged or violent" [OED].
movable (adj.): also moveable, late 14c., "disposed to movement;" c. 1400, "capable of being moved," from Old French movable, from moveir (see move (v.)). A moveable feast (early 15c.) is one in the Church calendar which, though always on the same day of the week, varies its date from year to year. Related: Movability.
move (v.): late 13c., from Anglo-French mover, Old French movoir "to move, get moving, set out; set in motion; introduce" (Modern French mouvoir), from Latin movere "move, set in motion; remove; disturb" (past participle motus, frequentative motare), from PIE root *meue- "to push away" (source also of Sanskrit kama-muta "moved by love" and probably mivati "pushes, moves;" Lithuanian mauti "push on;" Greek ameusasthai "to surpass," amyno "push away").

Intransitive sense developed in Old French and came thence to English, though it now is rare in French. Meaning "to affect with emotion" is from c. 1300; that of "to prompt or impel toward some action" is from late 14c. Sense of "to change one's place of residence" is from 1707. Meaning "to propose (something) in an assembly, etc.," is first attested mid-15c. Related: Moved; moving.
move (n.): mid-15c., "proposal," from move (v.). From 1650s in the gaming sense. Meaning "act of moving" is from 1827. Phrase on the move "in the process of going from one place to another" is from 1796; get a move on "hurry up" is Americal English colloquial from 1888 (also, and perhaps originally, get a move on you).
movement (n.): late 14c., from Old French movement "movement, exercise; start, instigation" (Modern French mouvement), from Medieval Latin movimentum, from Latin movere (see move (v.)). In the musical sense of "major division of a piece" it is attested from 1776; in the political/social sense, from 1828. Related: Movements.
mover (n.): late 14c., agent noun from move (v.). Originally of God. Meaning "one who moves goods as a profession" is from 1838.
movie (n.): 1912 (perhaps 1908), shortened form of moving picture in the cinematographic sense (1896). As an adjective from 1913. Movie star attested from 1913. Another early name for it was photoplay.
movies (n.): "moving pictures," 1912, see movie.
mow (v.): Old English mawan "to mow" (class VII strong verb; past tense meow, past participle mawen), from Proto-Germanic *mæanan (source also of Middle Low German maeyen, Dutch maaien, Old High German maen, German mähen "to mow," Old English mæd "meadow"), from PIE root *me- (4) "to mow, to cut grass or grain" (source also of poetic Greek amao, Latin metere "to reap, mow, crop," Italian mietere, Old Irish meithleorai "reapers," Welsh medi). Related: Mowed; mown; mowing.
mow (n.): "stack of hay," Old English muga, muwa "a heap, swath of corn, crowd of people," earlier muha, from Proto-Germanic *mugon (source also of Old Norse mugr "a heap," mostr "crowd"), of uncertain origin.
mower (n.): early 14c., agent noun from mow (v.). Mechanical sense is from 1852.
moxie (n.): "courage," 1930, from Moxie, brand name of a bitter, non-alcoholic drink, 1885, perhaps as far back as 1876 as the name of a patent medicine advertised to "build up your nerve;" despite legendary origin stories put out by the company that made it, it is perhaps ultimately from a New England Indian word (it figures in river and lake names in Maine, where it is apparently from Abenaki and means "dark water"). Much-imitated in its day; in 1917 the Moxie Company won an infringement suit against a competitor's beverage marketed as "Proxie."