Online Etymology Dictionary

monetize (v.): 1880, "put into circulation as money," from Latin moneta "money" (see money) + -ize. Related: Monetized; monetizing.
money (n.): mid-13c., "coinage, metal currency," from Old French monoie "money, coin, currency; change" (Modern French monnaie), from Latin moneta "place for coining money, mint; coined money, money, coinage," from Moneta, a title or surname of the Roman goddess Juno, in or near whose temple money was coined; perhaps from monere "advise, warn" (see monitor (n.)), with the sense of "admonishing goddess," which is sensible, but the etymology is difficult. Extended early 19c. to include paper money.
It had been justly stated by a British writer that the power to make a small piece of paper, not worth one cent, by the inscribing of a few names, to be worth a thousand dollars, was a power too high to be entrusted to the hands of mortal man. [John C. Calhoun, speech, U.S. Senate, Dec. 29, 1841]

I am not interested in money but in the things of which money is the symbol. [Henry Ford]
To make money "earn pay" is first attested mid-15c. Highwayman's threat your money or your life first attested 1841. Phrase in the money (1902) originally meant "one who finishes among the prize-winners" (in a horse race, etc.). The challenge to put (one's) money where (one's) mouth is is first recorded 1942, American English. money-grub "one who is sordidly intent on amassing money" is from 1768. The image of money burning a hole in someone's pocket is attested from 1520s.
money-bag (n.): 1560s, from money + bag (n.). Meaning "rich person" is from 1818. Related: moneybags.
money-maker (n.): c. 1400, "one who coins money," from money + maker. Meaning "thing which yields profit" is from 1899.
money-pit (n.): "edifice or project requiring constant outlay of cash with little to show for it," 1986 (year of a movie of the same name); see money (n.) + pit (n.). Before that (1930s), it was used for the shaft on Oak Island, Nova Scotia, that supposedly leads to treasure buried by Capt. Kidd or some other pirate. "Whether that name refers to the treasure or the several million dollars spent trying to get the treasure out is unclear." [Popular Mechanics, Sept. 1976]
moneyed (adj.): "having money," mid-15c., from past participle of Middle English verb monien "to supply with money" (see money (n.)).
moneyless (adj.): mid-14c., from money + -less.
moneyocracy (n.): 1834, from money + -cracy.
mong (prep.): c. 1200, shortened form of among.
monger (n.): Old English mangere "merchant, trader, broker," from mangian "to traffic, trade," from Proto-Germanic *mangojan (source also of Old Saxon mangon, Old Norse mangari "monger, higgler"), from Latin mango (genitive mangonis) "dealer, trader, slave-dealer," related to mangonium "displaying of wares." Not in Watkins, but Buck (with Tucker) describes it as "one who adorns his wares to give them an appearance of greater value" and writes it is probably a loan-word based on Greek manganon "means of charming or bewitching." Used in comb. form in English since at least 12c.; since 16c. chiefly with overtones of petty and disreputable.
monger (v.): 1928, from monger (n.). Not considered to be from Old English mangian. Related: Mongered; mongering (1846).
Mongol: 1738 (n.); 1763 (adj.), native name, said to be from mong "brave."
Mongolian: 1738 (adj.); 1846 (n.), from Mongol + -ian. As a classification for "the Asiatic race," it is from 1868.
Mongoloid: 1868 as a racial designation, from Mongol + -oid.
mongoloid: in reference to the genetic defect causing mental retardation (mongolism), 1899, from Mongoloid. So called for facial appearance. See Down's Syndrome. Such people were called Mongolian from 1866.
mongoose (n.): "snake-killing ichneumon of India," 1690s, perhaps via Portuguese, from an Indic language (such as Mahrathi mangus "mongoose"), probably ultimately from Dravidian (compare Telugu mangisu, Kanarese mungisi, Tamil mangus). The form of the English word altered by folk-etymology.
mongrel (n.): late 15c., "mixed-breed dog," from obsolete mong "mixture," from Old English gemong "mingling" (base of among), from Proto-Germanic *mangjan "to knead together" (see mingle). With pejorative suffix -rel. Meaning "person not of pure race" is from 1540s. As an adjective from 1570s.
monicker (n.): see moniker.
monies (n.): irregular plural of money that emerged mid-19c. in rivalry to earlier moneys (c. 1300).
moniker (n.): 1849, said to be originally a hobo term (but attested in London underclass from 1851), of uncertain origin; perhaps from monk (monks and nuns take new names with their vows, and early 19c. British tramps referred to themselves as "in the monkery"). Its origins seem always to have been obscure:
Sir H. Rawlinson can decipher cuneiform, but can he tell us why "moniker"--the word has a certain Coptic or Egyptian twang--means a name painted on a trunk? ["The Saturday Review," Dec. 19, 1857]
monism (n.): "the philosophical doctrine that there is only one principle," 1862, from Modern Latin monismus, from Greek monos "alone" (see mono-). First used in German by German philosopher Baron Christian von Wolff (1679-1754).
monist (n.): 1836, from Greek monos "single" (see mono-) + -ist. Also see monism. Related: Monistic.
monition (n.): "warning," late 14c., from Old French monition (13c.) and directly from Latin monitionem (nominative monitio) "warning, admonition, reminding," noun of action from past participle stem of monere "to warn" (see monitor (n.)).
monitor (n.): 1540s, "senior pupil at a school charged with keeping order, etc.," from Latin monitor "one who reminds, admonishes, or checks," also "an overseer, instructor, guide, teacher," agent noun from monere "to admonish, warn, advise," related to memini "I remember, I am mindful of," and to mens "mind," from PIE root *men- "to think" (see mind (n.)).

The type of lizard so called because it is supposed to give warning of crocodiles (1826). Meaning "squat, slow-moving type of ironclad warship" (1862) so called from name of the first vessel of this design, chosen by the inventor, Swedish-born U.S. engineer John Ericsson (1803-1889), because it was meant to "admonish" the Confederate leaders in the U.S. Civil War. Broadcasting sense of "a device to continuously check on the technical quality of a transmission" (1931) led to special sense of "a TV screen displaying the picture from a particular camera."
monitor (v.): 1818, "to guide;" 1924, "to check for quality" (originally especially of radio signals), from monitor (n.). General sense from 1944. Related: Monitored; monitoring.
monitory (adj.): late 15c., from Latin monitorius "admonishing," from monitus, past participle of monere (see monitor (n.)).
monk (n.): Old English munuc "monk" (used also of women), from Proto-Germanic *muniko- (source also of Old Frisian munek, Middle Dutch monic, Old High German munih, German Mönch), an early borrowing from Vulgar Latin *monicus (source of French moine, Spanish monje, Italian monaco), from Late Latin monachus "monk," originally "religious hermit," from Ecclesiastical Greek monakhos "monk," noun use of a classical Greek adjective meaning "solitary," from monos "alone" (see mono-). For substitution of -o- for -u-, see come.
In England, before the Reformation, the term was not applied to the members of the mendicant orders, who were always called friars. From the 16th c. to the 19th c., however, it was usual to speak of the friars as a class of monks. In recent times the distinction between the terms has been carefully observed by well-informed writers. In French and Ger. the equivalent of monk is applied equally to 'monks' and 'friars.' [OED]
monkey (n.): 1520s, likely from an unrecorded Middle Low German *moneke or Middle Dutch *monnekijn, a colloquial word for "monkey," originally a diminutive of some Romanic word, compare French monne (16c.); Middle Italian monnicchio, from Old Italian monna; Spanish mona "ape, monkey." In a 1498 Low German version of the popular medieval beast story Roman de Renart ("Reynard the Fox"), Moneke is the name given to the son of Martin the Ape; transmission of the word to English might have been via itinerant entertainers from the German states.

The Old French form of the name is Monequin (recorded as Monnekin in a 14c. version from Hainault), which could be a diminutive of some personal name, or it could be from the general Romanic word, which may be ultimately from Arabic maimun "monkey," literally "auspicious," a euphemistic usage because the sight of apes was held by the Arabs to be unlucky [Klein]. The word would have been influenced in Italian by folk etymology from monna "woman," a contraction of ma donna "my lady."

Monkey has been used affectionately for "child" since c. 1600. As a type of modern popular dance, it is attested from 1964. Monkey business attested from 1883. Monkey suit "fancy uniform" is from 1886. Monkey wrench is attested from 1858; its figurative sense of "something that obstructs operations" is from the notion of one getting jammed in the gears of machinery (compare spanner in the works). To make a monkey of someone is attested from 1900. To have a monkey on one's back "be addicted" is 1930s narcotics slang, though the same phrase in the 1860s meant "to be angry." There is a story in the Sinbad cycle about a tormenting ape-like creature that mounts a man's shoulders and won't get off, which may be the root of the term. In 1890s British slang, to have a monkey up the chimney meant "to have a mortgage on one's house." The three wise monkeys ("see no evil," etc.) are attested from 1926.
monkey (v.): 1859, "to mock, mimic," from monkey (n.). Meaning "play foolish tricks" is from 1881. Related: Monkeyed; monkeying.
monkey-shines (n.): also monkeyshines, "monkeyish behavior, tricks, antics," 1832 (in the "Jim Crow" song), from monkey (n.) + shine (n.) "a caper, trick" (1835), from an American English slang sense perhaps related to the expression cut a shine "make a fine impression" (1819); see slang senses under shine (n.). For sense of the whole word, compare Old French singerie "disreputable behavior," from singe "monkey, ape."
monkish (adj.): "pertaining to a monk," 1540s, from monk (n.) + -ish. Related: Monkishly; monkishness.
monkshood (n.): also monk's-hood, 1570s, from monk (n.) + hood (n.1). So called for the shape of the flowers.
mono: 1959 as a shortening of monophonic; earlier used among printers for "monotype machine" (c. 1925) and generally for monochrome (motorcar, etc.), 1940s. From 1964 as short for mononucleosis.
mono-: word-forming element meaning "one, alone; containing one (atom, etc.)," from Greek mono-, comb. form of monos "single, alone," from PIE root *men- "small, isolated" (source also of Greek manos "rare, sparse," Armenian manr "thin, slender, small," and perhaps English minnow).
monoceros (n.): c. 1300, "the unicorn," from Old French monoceros "unicorn," from Latin monoceros, from Greek monokeros, from mono- "single" (see mono-) + keras "horn of an animal," from PIE *ker- (1) "horn, head" (see horn (n.)).
This is a modern constellation, generally supposed to have been first charted by Bartschius as Unicornu; but Olbers and Ideler say that it was of much earlier formation, the latter quoting allusions to it, in the work of 1564, as "the other Horse south of the Twins and the Crab"; and Scaliger found it on a Persian sphere. [Richard Hinckley Allen, "Star Names and Their Meanings," London: 1899]
monochromatic (adj.): 1807, from mono- + chromatic, or from monochrome + -atic. Related: Monochromatically (1784).
monochrome (n.): 1660s, "painting or drawing done in different tints of a single color," from Greek monochromos "of a single color," from monos "single, alone" (see mono-) + khroma (genitive khromatos) "color, complexion, skin" (see chroma). As an adjective from 1849. Photographic sense is recorded from 1940.
monocle (n.): "single eyeglass," 1886, from French monocle, noun use of adjective monocle "one-eyed, blind in one eye" (13c.), from Late Latin monoculus "one-eyed," from Greek monos "single, alone" (see mono-) + Latin oculus "eye" (see eye (n.)).
That this, a hybrid, a Gallicism, and a word with no obvious meaning to the Englishman who hears it for the first time, should have ousted the entirely satisfactory eyeglass is a melancholy illustration of the popular taste in language. [Fowler]
monocular (adj.): 1630s, from Late Latin monoculus "one-eyed," from Greek monos "alone, single" (see mono-) + Latin oculus "eye" (see eye (n.)).
monoculture (n.): "cultivation of a single crop when others are possible," 1915, from mono- "single" + culture (n.).
monogamous (adj.): "having but one wife or husband at a time," 1770, from Medieval Latin monogamus, from Greek monogamos "marrying only once" (see monogamy).
monogamy (n.): 1610s, from French monogamie, from Late Latin monogamia, from Greek monogamia, from monogamos "marrying only once," from monos "single, alone" (see mono-) + gamos "marriage" (see gamete).
monogeny (n.): "theory that humankind originated from a single pair of ancestors," 1865; see mono- + -geny.
monogram (n.): "two or more letters intertwined," 1690s, from French monogramme or directly from Late Latin monogramma (5c.), from Late Greek monogrammon "a character formed of several letters in one design," especially in reference to the signature of the Byzantine emperors, noun use of neuter of monogrammos (adj.) "consisting of a single letter," literally "drawn with single lines," from Greek monos "single, alone" (see mono-) + gramma "letter, line, that which is drawn or written" (see -gram). Earlier it meant "sketch or picture drawn in lines only, without shading or color," a sense also found in Latin and probably in Greek. Related: Monogrammatic.
monogram (v.): 1868, from monogram (n.). Related: Monogrammed; monogramming.
monograph (n.): "treatise on a single subject," 1821, from mono- + -graph "something written." Earlier was monography (1773).
monokini (n.): 1964, from mono- + bikini, on mistaken notion that the bi- element was the Greek prefix meaning "two."
monolith (n.): "column consisting of a single large block of stone," 1848, from French monolithe (16c.), from Latin monolithus (adj.) "consisting of a single stone," from Greek monolithos "made of one stone," from monos "single, alone" (see mono-) + lithos "stone." Transferred and figurative use is from 1934.
monolithic (adj.): 1825, "formed of a single block," from monolith + -ic. Figurative use from 1920.
monologue (n.): 1660s, "long speech by one person," from French monologue, from Late Greek monologos "speaking alone," from Greek monos "single, alone" (see mono-) + logos "speech, word," from legein "to speak" (see lecture (n.)).