Online Etymology Dictionary

lamp-shade (n.): also lampshade, 1829, from lamp + shade (n.).
lamplight (n.): also lamp-light, late 14c., from lamp + light (n.).
lampoon (v.): 1650s, from lampoon (n.), or else from French lamponner, from the Middle French noun. Related: Lampooned; lampooning.
lampoon (n.): 1640s, from French lampon (17c.), of unknown origin, said by French etymologists to be from lampons "let us drink," popular refrain for scurrilous 17c. songs, from lamper "to drink, guzzle," a nasalized form of laper "to lap," from a Germanic source akin to lap (v.). Also see -oon.
lamprey (n.): c.1300 (c.1200 as a surname?), from Old French lamproie, from Medieval Latin lampreda, from Late Latin lampetra "lamprey," of uncertain origin, usually explained as literally "lick-rock," from Latin lambere "to lick" (see lap (v.1)) + petra "rock" (see petrous). The animals attach themselves to things with their sucker-like mouths.
Lancaster: Loncastre (1086) "Roman Fort on the River Lune," a Celtic river name probably meaning "healthy, pure." The Lancastrians in the War of the Roses took their name from their descent from John of Gaunt, Duke of Lancaster.
lance (n.): late 13c. (late 12c. as a surname), from Old French lance (12c.), from Latin lancea "light spear, Spanish lance" (Italian lancia, Spanish lanza), possibly of Celt-Iberian origin. The French word spread into Germanic (cf. German Lanze, Middle Dutch lanse, Dutch lans, Danish landse). Lance corporal (1786) is from obsolete lancepesade "officer of lowest rank" (1570s), from Old Italian lancia spezzata "old soldier," literally "broken lance."
lance (v.): "to pierce with a lance," c.1300, from Old French lancier, from Late Latin lanceare "wield a lance; pierce with a lance," from lancea (see lance (n.)). The surgical sense (properly with reference to a lancet) is from late 15c. Related: Lanced; lancing.
Lancelot: masc. proper name, Old French, a double-diminutive of Frankish Lanzo, a hypocoristic name formed from some one of the Germanic names in Land-; cf. Old English Landbeorht "land-bright," in Old French Lambert.
lancer (n.): 1580s, "soldier armed with a lance," from French lancier, from Old French lance (see lance (n.)).
lancet (n.): late 14c., launcet, from Old French lancette "small lance" (12c.), diminutive of lance (see lance (n.)).
land (n.): Old English land, lond, "ground, soil," also "definite portion of the earth's surface, home region of a person or a people, territory marked by political boundaries," from Proto-Germanic *landom (cf. Old Norse, Old Frisian Dutch, German, Gothic land), from PIE *lendh- "land, heath" (cf. Old Irish land, Middle Welsh llan "an open space," Welsh llan "enclosure, church," Breton lann "heath," source of French lande; Old Church Slavonic ledina "waste land, heath," Czech lada "fallow land").

Etymological evidence and Gothic use indicates the original sense was "a definite portion of the earth's surface owned by an individual or home of a nation." Meaning early extended to "solid surface of the earth," which had been the sense of the root of Modern English earth. Original sense of land in English is now mostly found under country. To take the lay of the land is a nautical expression. In the American English exclamation land's sakes (1846) land is a euphemism for Lord.
land (v.1): "to bring to land," early 13c., from land (n.). Originally of ships; of fish, in the angling sense, from 1610s; hence figurative sense of "to obtain" (a job, etc.), first recorded 1854. Of aircraft, attested from 1916. Related: Landed; landing.
land (v.2): "to make contact, to hit home" (of a blow, etc.), by 1881, perhaps altered from lend in a playful sense, or else an extension of land (v.1).
landau (n.): type of four-wheeled carriage, 1743, from Landau, town in Bavaria where they first were made. The first element is the common Germanic element found in English land (n.); the identity of the second is disputed. But Klein says the vehicle name is "in reality" Spanish lando "originally a light four-wheeled carriage drawn by mules," from Arabic al-andul.
landed (adj.): "possessed of land," late Old English gelandod; see land (n.).
landfall (n.): "sighting of land," 1620s, also "the first land 'made' on a sea voyage;" from land (v.1) + fall (v.) in the sense of "happen." From the days of imprecise nautical navigation.
Land-fall. The first land discovered after a sea voyage. Thus a good land fall implies the land expected or desired; a bad landfall the reverse. [John Hamilton Moore, "The New Practical Navigator," London, 1814]
Of hurricanes, by 1932.
landfill (n.): 1916, from land (n.) + fill (n.). A euphemism for dump.
landform (n.): 1893; see land (n.) + form (n.). Perhaps immediately from German Landform.
landing (n.): c.1600, place for boats; of stairs, first attested 1789; from present participle of land (v.1).
landlady (n.): 1520s, from land (n.) + lady.
landline (n.): also land-line, by 1861, originally a telegraph wire run over land (as opposed to under sea); from land (n.) + line (n.). In modern use (by 1965), a telephone line which uses wire or some other material (distinguished from a radio or cellular line).
landlocked (adj.): 1620s, from land (n.) + past participle of lock (v.).
landlord (n.): early 15c. in modern usage, from land (n.) + lord (n.).
landlubber (n.): also land-lubber, sailor's term of contempt for a landsman, c.1700, from land (n.) + lubber (q.v.).
landmark (n.): Old English landmearc, from land (n.) + mearc (see mark (n.1)). Originally "object set up to mark the boundaries of a kingdom, estate, etc.;" general sense of "conspicuous object in a landscape" is from 1560s. Modern figurative sense of "event, etc., considered a high point in history" is from 1859.
landscape (n.): c.1600, "painting representing natural scenery," from Dutch landschap, from Middle Dutch landscap "region," from land "land" (see land) + -scap "-ship, condition" (see -ship). Originally introduced as a painters' term. Old English had cognate landscipe, and cf. Old High German lantscaf, German Landschaft, Old Norse landskapr. Meaning "tract of land with its distinguishing characteristics" is from 1886.
landscape (v.): "to lay out lawns, gardens, etc., plant trees for the sake of beautification," by 1916, from landscape (n). Related: Landscaped; landscaping.
landscaping (n.): by 1861; see landscape (v.).
The question, however, is, Can landscape-gardening (or short and sweet, landscaping) be taught? It, plainly, cannot. ["The Gardener's Monthly" July 1861]
Also of artists, "depiction as a landscape" (1868).
landslide (n.): 1856, American English, from land (n.) + slide (n.). Earlier was landslip, still preferred in Britain. Old English used eorðgebyrst in this sense; literally "earth-burst." In the political sense, landslide "lopsided electoral victory" is attested from 1888.
landslip (n.): 1670s, from land (n.) + slip (n.).
landwehr (n.): German military reserves, from German Landwehr, from Old High German lantweri, from lant "land" (see land (n.)) + weri "protection" (see weir).
lane (n.): Old English lane, lanu "narrow hedged-in road," common Germanic (cf. Old Frisian lana, Middle Dutch lane, Dutch laan "lane," Old Norse lön "row of houses"), of unknown origin. As one track of a marked road, from 1921, American English.
lang syne: c.1500, Scottish variant of long since; popularized in Burns' song, 1788.
language (n.): late 13c., langage "words, what is said, conversation, talk," from Old French langage (12c.), from Vulgar Latin *linguaticum, from Latin lingua "tongue," also "speech, language" (see lingual). The form with -u- developed in Anglo-French. Meaning "a language" is from c.1300, also used in Middle English of dialects:
Mercii, þat beeþ men of myddel Engelond[,] vnderstondeþ bettre þe side langages, norþerne and souþerne, þan norþerne and souþerne vnderstondeþ eiþer oþer. [John of Trevisa, translation of Bartholomew de Glanville's "De proprietatibus rerum," 1398]

In oþir inglis was it drawin, And turnid ic haue it til ur awin Language of the norþin lede, Þat can na noþir inglis rede. ["Cursor Mundi," early 14c.]
Language barrier attested from 1933.
languedoc (n.): "language of medieval France south of the Loire," 1660s, from French langue d'oc "speech of the south of France," literally "the language of 'yes,' " from oc the word used for "yes" in southern France, from Latin hoc "this;" as opposed to langue d'oïl, from the way of saying "yes" in the north of France (Modern French oui); each from a different word in Latin phrase hoc ille (fecit) "this he (did)." The langue d'oïl has developed into standard Modern French.
languet (n.): early 15c., literally "little tongue," from French languette, diminutive of langue "tongue," from Latin lingua (see lingual).
languid (adj.): 1590s, from Middle French languide (16c.) and directly from Latin languidus "faint, listless," from languere "be weak or faint," from PIE root *(s)leg- "to be slack" (see lax). Related: Languidly; languidness.
languish (v.): early 14c., "fail in strength, exhibit signs of approaching death," from languiss-, present participle stem of Old French languir "be listless, pine, grieve, fall ill," from Vulgar Latin *languire, from Latin languere "be weak or faint" (see lax). Weaker sense "be lovesick, grieve, lament, grow faint," is from mid-14c. Related: Languished; languishing.
languor (n.): c.1300, "disease, distress, mental suffering," from Old French langor "sickness, weakness" (Modern French langueur), from Latin languorem (nominative languor) "faintness, feebleness, lassitude," from languere "be weak or faint" (see lax). Sense shifted to "faintness, weariness" (1650s) and "habitual want of energy" (1825).
languorous (adj.): late 15c., "mournful," from Old French langoros (11c.), from langor (see languor). Meaning "suggestive of languor" is from 1821. Related: Languorously; languorousness.
Lanier: surname, from Old French lainier "wool-monger," from Latin lana "wool" (see wool).
lank (adj.): Old English hlanc "loose and empty, slender, flaccid," from Proto-Germanic *khlankaz, perhaps from a root meaning "flexible" (cf. German lenken "to bend, turn aside," Old Norse hlykkr "bend, noose, loop"), from PIE root *kleng- "to bend, turn" (see link (n.)). "Some examples may be long adj. with unvoicing of g" ["Middle English Dictionary"]
lanky (adj.): 1630s, "straight and flat," used of hair, from lank + -y (2); sense of "awkwardly tall and thin" is first recorded 1818. Related: Lankiness.
lanolin (n.): fatty matter extracted from sheep's wool," 1885, from German Lanolin, coined by German physician Mathias Eugenius Oscar Liebreich (1838-1908) from Latin lana "wool" (see wool) + oleum "oil, fat" (see oil (n.)) + chemical suffix -in (2).
lantern (n.): mid-13c., from Old French lanterne "lamp, lantern, light" (12c.), from Latin lanterna "lantern, lamp, torch," altered (by influence of Latin lucerna "lamp") from Greek lampter "torch," from lampein "to shine" (see lamp). Variant lanthorn (16c.-19c.) was folk etymology based on the common use of horn as a translucent cover. Lantern-jaws "hollow, long cheeks" is from a resemblance noted since at least mid-14c.
lanthanum (n.): metallic rare earth element, 1841, coined in Modern Latin by Swedish chemist and mineralogist Carl Gustav Mosander (1797-1858), who discovered it in 1839, from Greek lanthanein "to lie hidden, escape notice," from PIE root *ladh- "to be hidden" (see latent). So called because the element was "concealed" in rare minerals.
lanyard (n.): also laniard, alternative spelling (influenced by nautical yard (2) "long beam used to support a sail") of Middle English lainer, "thong for fastening parts of armor or clothing" (late 14c.), from Old French laniere "thong, lash," from lasniere, from lasne "strap, thong," apparently altered (by metathesis and influence of Old French las "lace") from nasliere, from Frankish *nastila or some other Germanic source, from Proto-Germanic *nastila- (cf. Old High German, Old Saxon nestila "lace, strap, band," German nestel "string, lace, strap"), from PIE root *ned- "to knot."
Laocoon: Trojan priest of Apollo, from Latin Laocoon, from Greek Laukoun, from laos "people" (see lay (adj.)) + koeo "I mark, perceive."
Laocoön, n. A famous piece of antique sculpture representing a priest of that time and his two sons in the folds of two enormous serpents. The skill and diligence with which the old man and lads support the serpents and keep them up in their work have been justly regarded as one of the noblest artistic illustrations of the mastery of human intelligence over brute inertia. [Ambrose Bierce, "Devil's Dictionary," 1911]
Laodicean: "lukewarm in religion," 1560s, from Laodicea, Syrian city (modern Latakia) whose early Christians were chastised in the Bible for indifference to their religion [Rev. iii:14-16]. The city is said to be named for the 3c B.C.E. Syrian queen Laodice, wife of Antiochus II.