LSD Look up LSD at Dictionary.com
"lysergic acid diethylamide," 1950 (as LSD 25), from German LSD (1947), from letters in Lysergsäure-diäthylamid, the German form of the chemical name. For first element, see lysergic. German säure "acid" is cognate with English sour (adj.).
Ltd. Look up Ltd. at Dictionary.com
abbreviation of limited, attested by 1900.
luau (n.) Look up luau at Dictionary.com
Hawaiian party or feast, 1853, from Hawaiian lu'au, literally "young taro tops," which were served at outdoor feasts.
lubber (n.) Look up lubber at Dictionary.com
mid-14c., "big, clumsy, stupid fellow who lives in idleness," from lobre, earlier lobi "lazy lout," probably of Scandinavian origin (compare Swedish dialectal lubber "a plump, lazy fellow"). But OED suggests a possible connection with Old French lobeor "swindler, parasite," with sense altered by association with lob (n.) in the "bumpkin" sense. Sometimes also Lubbard (1580s), with pejorative suffix -ard.

Since 16c. mainly a sailors' word for those inept or inexperienced at sea (as in landlubber), but earliest attested use is of lazy monks (abbey-lubber). Compare also provincial English lubberwort, name of the mythical herb that produces laziness (1540s), Lubberland "imaginary land of plenty without work" (1590s).
lubber (v.) Look up lubber at Dictionary.com
"to sail clumsily; to loaf about," 1520s, from lubber (n.). Related: Lubbered; lubbering.
lubberly (adj.) Look up lubberly at Dictionary.com
"clumsy, awkward; coarse," 1570s, from lubber (n.) + -ly (1).
lube Look up lube at Dictionary.com
1934, colloquial shortening of lubrication (n.); as a verb, short for lubricate, by 1961.
Lubish (adj.) Look up Lubish at Dictionary.com
16c. of money; c. 1600 of beer, "from Lubeck," the Hanseatic city in northern Germany, from German lübisch, Dutch lubeksch (adj.), from Lübeck. Formerly a trade center, hence its use as an adjective in English. The city was founded 1143 and is said to be named for the former principality of the Liubichi, literally "the people of prince Liub" (literally "beloved").
lubric (adj.) Look up lubric at Dictionary.com
late 15c., "smooth, slippery," also "lascivious, lewd," from Middle French lubrique (15c.) or directly from Latin lubricus "slippery," figuratively "seductive," from PIE *sleubh- "to slip, slide" (see sleeve). Related: Lubrical.
lubricant (n.) Look up lubricant at Dictionary.com
"material that can reduce friction in rubbing surfaces," 1828, probably from lubricant (adj.), or else from Latin lubricantem.
lubricant (adj.) Look up lubricant at Dictionary.com
"reducing friction," 1809, from Latin lubricantem (nominative lubricans), present participle of lubricare "to make slippery or smooth," from lubricus "slippery; easily moved, sliding, gliding;" figuratively "uncertain, hazardous, dangerous; seductive," from PIE *leubh-ro-, suffixed form of root *sleubh- "to slip, slide" (see sleeve).
lubricate (v.) Look up lubricate at Dictionary.com
1620s, "make slippery or smooth" (especially by the application of an oil), from Latin lubricatus, past participle of lubricare "to make slippery or smooth," from lubricus "slippery; easily moved, sliding, gliding;" figuratively "uncertain, hazardous, dangerous; seductive," from PIE *sleubh- "to slip, slide" (see sleeve). Related: Lubricated; lubricating. Earlier verb was lubrify (1610s), from Medieval Latin lubrificare.
lubrication (n.) Look up lubrication at Dictionary.com
1640s, "act of lubricating," noun of action from lubricate (v.). Earlier was lubrifaction (1540s). Lubrification is from 1690s.
lubricity (n.) Look up lubricity at Dictionary.com
late 15c., "lasciviousness," from Middle French lubricité or directly from Medieval Latin lubricitatem (nominative lubricitas) "slipperiness," from Latin lubricus "slippery; easily moved, sliding, gliding;" figuratively "uncertain, hazardous, dangerous; seductive," from PIE *sleubh- "to slip, slide" (see sleeve). Sense of "oiliness, smoothness" in English is from 1540s; figurative sense of "shiftiness" is from 1610s.
The priests had excellent cause to forbid us lechery: this injunction, by reserving to them acquaintance with and absolution for these private sins, gave them an incredible ascendancy over women, and opened up to them a career of lubricity whose scope knew no limits. [Marquis de Sade, "Philosophy in the Bedroom"]
lubricous (adj.) Look up lubricous at Dictionary.com
1530s, "lascivious," from Latin lubricus "slippery, slimy, smooth," figuratively "seductive," from PIE *sleubh- "to slip, slide" (see sleeve). Literal meaning "slippery, oily" is from 1650s in English; figurative sense of "shifty, elusive" is from 1640s. Also lubricious (1580s).
lubritorium (n.) Look up lubritorium at Dictionary.com
"place where automobiles are greased," 1928; from lubrication + ending from auditorium. The -torium in the word was an overworked trade suffix in the late 1920s; Mencken lists also infantorium, shavatorium, restatorium, hatatorium, and odditorium ("a slide-show").
Lucca Look up Lucca at Dictionary.com
city and region in Italy, formerly an independent state. Anglicized in Middle and early Modern English as Luke. Noted in England for olive oil and lambskins used in hat-making. Related: Lucchese (adj.), the Italian form, alongside English Luccan (mid-15c.).
lucency (n.) Look up lucency at Dictionary.com
"brightness, luster, luminosity," 1650s, from lucent + -cy. Lucence is from late 15c.
lucent (adj.) Look up lucent at Dictionary.com
mid-15c., "shining, bright, luminous," from Latin lucentem (nominative lucens), present participle of lucere "to shine, glow, be bright," from PIE root *leuk- "light, brightness" (see light (n.)). Meaning "translucent, clear" is from 1820. Related: Lucently.
lucern (adj.) Look up lucern at Dictionary.com
"pertaining to the lynx," 1530s, from German lüchsern, from luchs "lynx" (see lynx), or else from Old French loucerve (see serval).
Lucia Look up Lucia at Dictionary.com
fem. proper name; see Lucy.
Lucian Look up Lucian at Dictionary.com
masc. proper name, from Latin Lucianus (source also of French Lucien), a derivative of Roman Lucius, from lux (genitive lucis) "light" (see light (n.)). The Hellenistic Greek writer (c. 160 C.E., his name is Latinized from Greek Loukianos) was noted as the type of a scoffing wit. Hence Lucianist (1580s) in reference to that sort of writer; it also was "the name of two sorts of heretics" [OED].
lucid (adj.) Look up lucid at Dictionary.com
1590s, "bright, shining" (a sense now obsolete or restricted), from Latin lucidus "light, bright, clear," figuratively "perspicuous, lucid, clear," from lucere "to shine," from lux (genitive lucis) "light," from PIE root *leuk- "to shine, be bright" (see light (n.)).

Sense of "easy to understand, free from obscurity of meaning, marked by intellectual clarity" first recorded 1786. Lucid interval "period of calm or temporary sanity" (1580s) is from Medieval Latin lucida intervalla (plural), common in medieval legal documents (non est compos mentis, sed gaudet lucidis intervallis, etc.). The notion probably is of a period of calm and clear during a storm. Related: Lucidly; lucidness (1640s).
lucida (n.) Look up lucida at Dictionary.com
in astronomy, "star easily seen by the naked eye," also "brightest star in a constellation or group," 1727, from Modern Latin lucida (stella) "bright star," from fem. of Latin lucidus "light, bright, clear" (see lucid). Plural lucidae. Astronomy has used lucid for "visible to the naked eye" since 1690s.
lucidity (n.) Look up lucidity at Dictionary.com
1650s, "brightness," from French lucidité, from Late Latin luciditas, from Latin lucidus "light, bright, clear," from lucere "to shine" (see light (n.)). Meaning "intellectual clarity, transparency of expression" is by 1851.
Lucifer Look up Lucifer at Dictionary.com
Old English Lucifer "Satan," also "morning star, Venus in the morning sky before sunrise," also an epithet or name of Diana, from Latin Lucifer "morning star," noun use of adjective, literally "light-bringing," from lux (genitive lucis) "light" (see light (n.)) + ferre "to carry, bear" (see phoresy). Venus in the evening sky was Hesperus.

Belief that it was the proper name of Satan began with its use in Bible to translate Greek Phosphoros, which translates Hebrew Helel ben Shahar in Isaiah xiv.12 -- "How art thou fallen from heaven, O Lucifer, son of the morning!" [KJV] Because of the mention of a fall from Heaven, the verse was interpreted spiritually by Christians as a reference to Satan, even though it is literally a reference to the King of Babylon (see Isaiah xiv.4). Sometimes rendered daystar in later translations.

As "friction match," 1831, short for Lucifer match (1831). Among the 16c. adjectival forms were Luciferian, Luciferine, Luciferous. There was a noted Bishop Lucifer of Cagliari in Sardinia in the 4th century, a strict anti-Arian regarded locally as a saint.
luciferase (n.) Look up luciferase at Dictionary.com
enzyme found in fireflies and other glowing creatures, 1888, from French luciférase; see Lucifer. Related: Luciferin.
luciferous (adj.) Look up luciferous at Dictionary.com
"light-bringing, emitting light," 1650s, from Latin lucifer "light-bringing" (see Lucifer) + -ous. Figurative use "affording means of discovery" is earliest (1640s) and more common. Related: Luciferously.
lucifugous (adj.) Look up lucifugous at Dictionary.com
"shunning light" (in reference to bats, cockroaches, etc.), 1650s, from Latin lucifugus "light-shunning," from stem of lucere "to shine" (see light (n.)) + stem of fugax "apt to flee, timid," figuratively "transitory, fleeting," from fugere "to flee" (see fugitive (adj.)).
Lucille Look up Lucille at Dictionary.com
fem. proper name, from French Lucille, diminutive of Latin Lucia (see Lucy).
Lucina Look up Lucina at Dictionary.com
Roman goddess of childbirth, late 14c., from Latin Lucina, literally "she that brings to the light," fem. of lucinus, from luc-, stem of lux "light" (see light (n.)).
Lucite Look up Lucite at Dictionary.com
1937, proprietary name (E.I. DuPont de Nemours and Co., Wilmington, Delaware, U.S.) for a solid, transparent plastic, from Latin luc(i)-, from stem of lucere "to shine" (see light (n.)).
Lucius Look up Lucius at Dictionary.com
masc. proper name; see Lucian.
luck (n.) Look up luck at Dictionary.com
c. 1500, "fortune good or bad, what happens to one by chance (conceived as being favorable or not); good luck, quality of having a tendency to receive desired or beneficial outcomes," not found in Old English, probably from early Middle Dutch luc, shortening of gheluc "happiness, good fortune," a word of unknown origin. It has cognates in Modern Dutch geluk, Middle High German g(e)lücke, German Glück "fortune, good luck."

Perhaps first borrowed in English as a gambling term. To be down on (one's) luck is from 1832; to be in luck is from 1857; to push (one's) luck is from 1911. Good luck as a salutation to one setting off to do something is from 1805. Expression no such luck is from 1857. Better luck next time as an expression of encouragement in the face of disappointment is from 1858, but the expression itself is older:
A gentleman was lately walking through St Giles's, where a levelling citizen attempting to pick his pocket of a handkerchief, which the gentleman caught in time, and secured, observing to the fellow, that he had missed his aim, the latter, with perfect sang-froid, answered, "better luck next time master."  ["Monthly Mirror," London, 1802]
Luck of the draw (1967) is from card-playing. In expressions often ironical, as in just (my) luck (1909). To be out of luck is from 1789; to have one's luck run out is from 1966.
luck (v.) Look up luck at Dictionary.com
by 1945, from luck (n.). To luck out "succeed through luck" is American English colloquial, attested by 1946; to luck into (something good) is from 1944. Lukken (mid-15c.) was a verb in Middle English meaning "to happen, chance;" also "happen fortunately," but the modern word probably is a new formation.
luckily (adv.) Look up luckily at Dictionary.com
1520s, from lucky + -ly (2).
luckless (adj.) Look up luckless at Dictionary.com
1560s, from luck (n.) + -less. Related: Lucklessly; lucklessness.
lucky (adj.) Look up lucky at Dictionary.com
mid-15c., of persons; 1540s, of actions or objects, "likely to bring luck;" from luck (n.) + -y (2). Meaning "occurring by chance" is 1590s. Related: Luckier; luckiest; luckiness.

Lucky break is attested from 1884 in billiards; 1872 as "failure or break-down which turns out to be fortunate." Lucky dog "unusually lucky person" is from 1842. Lucky Strike as the name of a U.S. brand of cigarettes (originally chewing tobacco) popular in the World War II years is said to date from 1871. Its popularity grew from 1935 when the brand's maker picked up sponsorship of radio's "Your Hit Parade."
lucrative (adj.) Look up lucrative at Dictionary.com
early 15c., from Old French lucratif "profitable" and directly from Latin lucrativus "gainful, profitable," from lucratus, past participle of lucrari "to gain, win, acquire," from lucrum "gain, profit" (see lucre). Related: Lucratively; lucrativeness.
lucre (n.) Look up lucre at Dictionary.com
late 14c., from Old French lucre, from Latin lucrum "material gain, advantage, profit; wealth, riches," of uncertain origin. De Vaan says from Proto-Italic *lukro-, from PIE *lhu-tlo- "seizure, gain," with cognates in Greek apolauo "take hold of, enjoy," leia (Doric laia) "booty;" Gothic laun "reward." Filthy lucre (Titus i.11) is Tyndale's rendering of Greek aiskhron kerdos.
Lucretia Look up Lucretia at Dictionary.com
fem. proper name, from Latin Lucretia (source also of French Lucrèce), fem. of Lucretius, Roman masc. proper name, originally the name of a Roman gens.
Lucretius Look up Lucretius at Dictionary.com
Roman masc. proper name, originally the name of a Roman gens. The Epicurean philosopher-poet was Titus Lucretius Carus (c. 98-55 B.C.E.). Hence Lucretian (1712).
lucubrate (v.) Look up lucubrate at Dictionary.com
1620s, "to work at night," from Latin lucubratus, past participle of lucubrare "work at night, work by lamplight," from the stem of lucere "to shine" (see light (n.)). Hence "to write or study laboriously" (1804).
lucubration (n.) Look up lucubration at Dictionary.com
1590s, "close study or thought;" 1610s, "a product of such study or thought, literary work showing signs of too-careful elaboration," from Latin lucubrationem (nominative lucubratio) "nocturnal study, night work," noun of action from past participle stem of lucubrare, literally "to work by artificial light," from stem of lucere "to shine" (see light (n.)). Related: Lucubrations.
The current story in antiquity was that Aeschylus had been killed near Gela in Sicily by a tortoise dropt on his head by an eagle, which mistook the bald shiny pate of the venerable poet for a stone, and hoped to smash the tortoise on it. See Biographi Graeci, ed. Westermann, p. 120 ; Aelian Nat. Anim. vii. 16 ; Suidas, s.v. Αίσχύλοσ ; Valerius Maximus, ix. 12. Ext. 2. This important topic has produced the usual crop of learned dissertations. The late Professor F. G. Welcker gravely discussed it by the help of ornithological information derived from Aesop's fables, notes of travel made by the professor himself on the supposed scene of the catastrophe, and statistics as to the number of bald-headed men in antiquity. The interesting inquiry has since been prosecuted by other scholars with equal judgment and learning. The reader who desires to peruse these ponderous lucubrations should consult Rheinisches Museum, N.F. 7 (1850), pp. 139-144, 285 sq ; id., 9 (1854), pp. 148-155, 160* ; id., 37 (1882), pp. 308-312 ; Fleckeisen's Jahrbücher, 26 (1880), pp. 22-24 ; Welcker, Antike Denkmäler, 2. pp. 337-346. [J.G. Frazer, notes to Pausanias's "Description of Greece," 1898]
luculent (adj.) Look up luculent at Dictionary.com
early 15c., "luminous, bright;" 1590s, "evident, lucid," from Latin luculentus "full of light, bright, splendid," from the stem of lux "light" (see light (n.)).
lucus a non lucendo Look up lucus a non lucendo at Dictionary.com
"absurd etymology," generally "anything illogical, outrageous hypothesis," 1711, from the Latin phrase, taken as the outstanding example of such an error. "A grove (lucus) [is so called] from not (a non) being light (lucendo, ablative of lucere "to shine;" see light (n.))." That is, it is called a grove because light doesn't get into it. This explanation is found in a commentary on Virgil (Aeneid 1.22) by Servius, a 4th century grammarian, among other places. Other ancient grammarians (notably Quintilian) found it paradoxical and absurd.

Modern scholarship, however, concludes that lucus and lucere probably do both come from the same PIE root, meaning "light, bright." De Vaan writes: "Lucus 'sacred grove, wood,' from PIE *louk-o- 'light place,' with cognates in Sanskrit loka- 'free space, world,' Lithuanian laukas 'field, land,' Latvian lauks 'field, clearing in the woods,' Old High German loh 'clearing' and English lea 'open field, meadow, piece of untilled grassy ground.'" Apparently the primeval notion in *louk-o- was a lighter place in a thick forest. Migration, change of climate or felling of the woods might have shifted the meaning.
Lucy Look up Lucy at Dictionary.com
fem. proper name, from French Lucie, from Latin Lucia, fem. of Lucius (see Lucian).
Luddite (n.) Look up Luddite at Dictionary.com
also luddite, 1811, the name taken by an organized band of weavers in Midlands and northern England who for about 5 years thereafter destroyed machinery, for fear it would deprive them of work. Supposedly they got it from Ned Ludd, a Leicestershire worker who in 1779 had smashed two machines in a rage, but that story first was told in 1847. Applied by 1961 to modern spurners of automation and technology. As an adjective from 1812.
lude (n.) Look up lude at Dictionary.com
slang shortening of quaalude, by 1973.
ludic (adj.) Look up ludic at Dictionary.com
"spontaneously playful," 1940, a term in psychiatry, from French ludique, from Latin ludere "to play" (see ludicrous).