Online Etymology Dictionary

plausible: 1540s, "acceptable, agreeable," from L. plausibilis "deserving applause, acceptable," from pp. stem of plaudere "to applaud" (see plaudit). Meaning "having the appearance of truth" is recorded from 1560s.
play (v.): O.E. plegian "to exercise, frolic, perform music," from W.Gmc. *plegan (cf. M.Du. pleyen "to rejoice, be glad"), of uncertain origin. Opposed to work (v.) since late 14c. Playground is attested from 1780. Playmate is from 1640s in the innocent sense, from 1954 in the sexual sense; playboy "wealthy bon vivant" is from 1829; fem. equivalent playgirl is first recorded 1934. Plaything is from 1675. To play up "emphasize" is from 1909; to play down "minimize" is from 1930. To play with oneself "masturbate" is from 1896; play for keeps is from 1861, originally of marbles or other children's games with tokens. To play the (something) card is attested from 1886; to play fair is from c.1440. Play-dough is first recorded 1959. To play (something) safe is from 1911; to play favorites is attested from 1902. For play the field see field.
play (n.): O.E. plega (W.Saxon), plæga (Anglian) "recreation, exercise, any brisk activity" (the latter sense preserved in swordplay, etc.), from play (v.). Meaning "dramatic performance" is attested from early 14c. Meaning "free or unimpeded movement" is from 1650s. Sporting sense first attested 1868. Playwright first recorded 1680s; play-bill is from 1670s. Player is from late 14c. in general sense; pimps' word for themselves from 1974. Play-by-play is attested from 1927.
plaza: 1683, from Sp. plaza "square, place," from V.L. *plattia, from L. platea "courtyard, broad street" (see place (n.)).
plea: c.1215, "lawsuit," from Anglo-Fr. plai (c.1170), O.Fr. plait "lawsuit, decision, decree" (842), from M.L. placitum "lawsuit," in classical L., "opinion, decree," lit. "that which pleases, thing which is agreed upon," properly neut. pp. of placere (see please). Sense development seems to be from "something pleasant," to "something that pleases both sides," to "something that has been decided." Meaning "a pleading, an agreement in a suit" is attested from c.1381. Plea bargaining is first attested 1963. Common pleas (c.1215) originally were legal proceedings over which the Crown did not claim exclusive jurisdiction (as distinct from pleas of the Crown); later "actions brought by one subject against another."
plead: mid-13c., "make a plea in court," from Anglo-Fr. pleder, O.Fr. pleider, plaidier, "agreement, discussion, lawsuit," from M.L. placitare, from L.L. placitum (see plea). Sense of "request, beg" first recorded late 14c.
pleasant: 1320, from O.Fr. plaisant, prp. of plaisir "to please" (see please). Pleasantry "sprightly humor in conversation" (1655) is from Fr. plaisanterie, from O.Fr. plesanterie (13c.), from plaisant. It has the word's modern Fr. sense of "funny, jocular."
please (v.): early 14c., "to be agreeable," from O.Fr. plaisir (Fr. plaire) "to please," from L. placere "to be acceptable, be liked, be approved," related to placare "to soothe, quiet," from PIE base *p(e)lag- "to smooth, make even" (cf. Gk. plax, gen. plakos "level surface," plakoeis "flat;" Lett. plakt "to become flat;" O.N. flaga "layer of earth;" Norw. flag "open sea;" O.E. floh "piece of stone, fragment;" O.H.G. fluoh "cliff"). Intransitive sense (e.g. do as you please) first recorded c.1500; imperative use (e.g. please do this), first recorded 1620s, was probably a shortening of if it please (you) (late 14c.). Verbs for "please" supply the stereotype polite word ("Please come in," short for may it please you to ...) in many languages (Fr., It.), "But more widespread is the use of the first singular of a verb for 'ask, request' " [Buck, who cites Ger. bitte, Pol. prasze, etc.] Sp. favor is short for hace el favor "do the favor." Danish has in this sense vær saa god, lit. "be so good."
pleasure (n.): late 14c., "condition of enjoyment," from O.Fr. plesir "enjoyment, delight" (12c.), from plaisir (v.) "to please," from L. placere (see please (v.)). Ending altered in English 14c. by influence of words in -ure (measure, etc.). Meaning "sensual enjoyment as the chief object of life" is attested from 1520s. The verb meaning "to give pleasure to" is recorded from 1550s; sexual sense by 1610s. Related: Pleasured; pleasuring.
pleat: 1570, used as the verb version of plait (q.v.). Later (1581) as a noun.
plebe: "member of the lowest class at a U.S. military academy," 1833, probably a shortened form of plebian (q.v.), which in L. had the short form plebs or plebes.
plebian: 1533 (n.), 1566 (adj.), from L. plebius "of the common people," from plebes "the common people" (as opposed to patricians, etc.), perhaps from PIE base *ple- "to be full" (see plenary). Slang shortening pleb is attested from 1865 (see plebe).
plebiscite: "direct vote of the people," 1860 (originally in ref. to Italian unification), from Fr. plébiscite (1776 in modern sense), from L. plebiscitum "a decree or resolution of the people," from plebs (gen. plebis) "the common people" + scitum "decree," properly neuter pp. of sciscere "to assent, vote for, approve," inchoative of scire "to know" (see science). Used earlier (1533) in a purely Roman historical context.
plectrum: 1626, from L. plectrum, from Gk. plektron "thing to strike with" (pick for a lyre, cock's supr, spear point, etc.), from plek-, root of plessein "to strike."
pledge: mid-14c., "surety, bail," from O.Fr. plege (Fr. pleige) "hostage, security, bail," probably from Frank. *plegan "to guarantee," from a W.Gmc. root meaning "have responsibility for" (cf. O.Saxon plegan "vouch for," O.H.G. pflegan "to care for, be accustomed to," O.E. pleon "to risk, expose to danger"). Meaning "allegiance vow attested by drinking with another" is from 1630s. Sense of "solemn promise" first recorded 1814, though this meaning is from c.1400 in the verb. Weekley notes the "curious contradiction" in pledge "to toast with a drink" (1540s) and pledge "the vow to abstain from drinking" (1833). Noun meaning "student who has agreed to join a fraternity or sorority" dates from 1901.
Pleiades: 1388, the seven daughters of Atlas and Pleione, transformed by Zeus into seven stars, from L., from Gk. Pleiades, perhaps lit. "constellation of the doves" from a shortened form of peleiades, pl. of peleias "dove," from PIE base *pel- "dark-colored, gray." Or perhaps from plein "to sail," because the season of navigation begins with their heliacal rising. Mentioned by Hesiod (pre-700 B.C.E.), only six now are visible to most people; on a clear night a good eye can see nine (in 1579, well before the invention of the telescope, astronomer Moestlin correctly drew 11 Pleiades stars); telescopes reveal at least 500.
plein-air: 1894, from Fr. phrase en plein air, lit. "in the open air." The style developed among Fr. impressionists c.1870.
Pleistocene: "pertaining to the glacial period," 1839, coined by Lyell from Gk. pleistos "most" (superl. of polys "much;" see poly-) + kainos "new" (see recent).
plenary: 1510s, earlier plenar (late 13c.), from M.L. plenarius "entire, complete," from L. plenus "full," from PIE *ple- "to be full" (see poly-).
plenipotentiary: c.1645, from M.L. plenipotentiarius "having full power," from L. plenus "full" (see plenary) + potentem "powerful" (see potent).
plenitude: early 15c., from O.Fr. plenitude, from L. plenitudinem (nom. plenitudo) "abundance, completeness, fullness," from plenus "complete, full" (see plenary).
plenteous: c.1300, from O.Fr. plentiveus "fertile, rich" (c.1220), from plentif "abundant," from plenté "abundance" (see plenty).
plenty: early 13c., from O.Fr. plentet (12c., Mod.Fr. dial. plenté), from L. plenitatem (nom. plenitas) "fullness," from plenus "complete, full" (see plenary). The colloquial adv. meaning "very much" is first attested 1842. Plentiful is first recorded late 15c.
plenum: 1678, "filled space" (opposite of vacuum), from L. plenum (spatium) "full (space)," neuter of plenus "complete, full" (see plenary). The meaning "of a full assembly of legislators" is first recorded 1772.
pleonasm: "redundancy in words," 1586, from L.L. pleonasmus, from Gk. pleonasmos, from pleonasein "to be more than enough," from pleon "more," comp. of polys "much," from PIE *ple- (see poly-).
plesiosaurus: 1825, from Mod.L. (1821), coined by William Daniel Conybeare (1787-1857) from Gk. plesios "near" + sauros "lizard."
plethora: 1540s, a medical word for "excess of body fluid," from L.L. plethora, from Gk. plethore "fullness," from plethein "be full" (see poly-). Figurative meaning "too much, overfullness in any respect" is first recorded 1700.
pleurisy: late 14c., from O.Fr. pleurisie (13c.), from L.L. pleurisis "pleurisy" (c.400), alt. of L. pleuritis "pain in the side," from Gk. pleuritis, from pleura "side of the body, rib," of unknown origin. Spelling alt. in L.L. on model of L. stem plur- "more" (cf. M.L. pluritas "multitude"), as if in ref. to "excess of humors."
Plexiglas: 1935, proprietary name (Röhm & Haas) for a substance also sold as Perspex and Lucite.
plexus: 1682, Mod.L., lit. "braid, network," from pp. of L. plectere "to twine, braid, fold," used of a network, such as solar plexus "network of nerves in the abdomen" (see solar).
pliable: late 15c., from O.Fr. pliable "flexible," from plier "to bend" (see ply (n.)).
pliant: c.1300, from O.Fr. pliant "bending" (13c.), prp. of plier "to bend" (see ply (n.)). Figurative sense of "easily influenced" is from c.1400.
plie: in ballet, 1892, from Fr. plié, lit. "to bend," from O.Fr. plier (see ply (n.)).
pliers: 1568, formed from ply (n.). Fr. cognate plieur meant "folder."
plight (v.): "pledge," obsolete except in archaic plight one's troth, from O.E. pligtan "endanger," verb form of pliht "danger, risk," from P.Gmc. *pleg- (cf. O.E. pleon "to risk the loss of, expose to danger," O.Fris., M.Du. plicht "care, carefulness," O.H.G. pfliht, Ger. pflicht "obligation, duty," M.Du. plien "to answer for, guarantee").
plight (n.): "condition or state (usually bad)," c.1175, from Anglo-Fr. plit, O.Fr. pleit "condition" (13c.), originally "way of folding," from V.L. *plictum, from L. plicitum, neut. pp. of L. plicare "to fold, lay" (see ply (v.)). Originally in neutral sense (as in modern Fr. en bon plit "in good condition"), sense of "harmful state" is probably from convergence with plight (v.) via notion of "entangling risk, pledge or promise with great risk to the pledger."
Plimsoll: "mark on the hull of a British ship showing how deeply she may be loaded," 1881, from Samuel Plimsoll (1824-98), M.P. for Derby and advocate of shipping reform (which were embodied in the Merchant Shipping Act of 1876). Sense extended 1907 to "rubber-soled canvas shoe" (equivalent of Amer.Eng. sneakers) because the band around the shoes that holds the two parts together reminded people of a ship's Plimsoll line; sense perhaps reinforced by sound assoc. with sole.
plinth: 1611, from Fr. plinthe, from L. plinthus, from Gk. plinthos "brick, squared stone," cognate with O.E. flint (see flint).
Pliocene: 1833, from Gk. pleion "more" + kainos "new" (see recent).
plod: 1562, of uncertain origin, perhaps imitative of the sound of walking heavily or slowly. Plodding "diligent and dull" is attested from 1589.
plop (v.): 1821, imitative of the sound of a smooth object dropping into water.
plosive: "type of consonantal sound," 1899, from (ex)plosive (q.v.).
plot: O.E. plot "small piece of ground," of unknown origin. Sense of "ground plan," and thus "map, chart" is 1551; that of "plan, scheme" is 1587, probably by accidental similarity to complot, from O.Fr. complot "combined plan," of unknown origin, perhaps a back-formation from compeloter "to roll into a ball." Meaning "set of events in a story" is from 1649. The verb is first attested 1589 in the sense of "to lay plans for" (usually with evil intent); 1590 in the lit. sense of "to make a map or diagram."
plough: see plow.
plover: 1304, from Anglo-Fr. plover, O.Fr. pluvier, earlier plovier (c.1200), from V.L. *plovarius, lit. "belonging to rain," from L. pluvia "rain." Perhaps so called because the birds' migration arrival coincides with the start of the rainy season, or from its supposed restlessness when rain approaches.
plow (n.): O.E. plog, ploh "plow, plowland (a measure of land)," possibly from Scand. (cf. O.N. plogr "plow"), from P.Gmc. *plogo- (cf. O.Fris. ploch, M.L.G. ploch, M.Du. ploech, O.H.G. pfluog). O.C.S. plugu, Lith. plugas "plow" are Germanic loan-words, as is probably L. plovus, plovum "plow," a word said by Pliny to be of Rhaetian origin. Replaced O.E. sulh, cognate with L. sulcus "furrow." As a name for the Big Dipper, it is recorded from 1513. The verb is first recorded c.1420. Plowshare is first recorded c.1380.
ploy: 1722, "anything with which one amuses oneself," Scottish and northern England dialect, possibly a shortened form of employ or deploy. Popularized in the sense "move or gambit made to gain advantage" by British humorist Stephen Potter (1900-1969).
pluck (v.): late O.E. ploccian "pull off, cull," from W.Gmc. *plokken (cf. M.L.G. plucken, M.Du. plocken, Flem. plokken), perhaps from V.L. *piluccare (cf. O.Fr. peluchier, c.1180), a frequentative, ultimately from L. pilare "pull out hair," from pilus "hair." But despite the similarities, OED finds difficulties with this and cites gaps in historical evidence. Noun sense of "courage, boldness" (1785) is originally boxing slang, from meaning "heart, viscera" (1611) as that which is "plucked" from slaughtered livestock. Perhaps infl. by fig. use in pluck up (one's courage, etc.), attested from c.1300. Hence, plucky (1842).
"To pluck a rose, an expression said to be used by women for going to the necessary house, which in the country usually stands in the garden." [F. Grose, "Classical Dictionary of the Vulgar Tongue," 1785]
This euphemistic use is attested from 1613.
plug: 1627, originally a seamen's term, probably from Du. plug, from M.Du. plugge "bung, stopper," related to Norw. plugg, Dan. pløg, M.L.G. pluck, Ger. pflock, ultimate origin uncertain. Sense of "wad or stick of tobacco" is attested from 1728. Electrical sense is from 1883; meaning "sparking device in an internal combustion engine" is from 1886. The verb meaning "to close tightly (a hole), to fill" is first recorded 1630. Meaning "advertisement" first recorded 1902, perhaps from verb sense "work energetically at" (c.1865). The noun sense of "advertisement" is from 1902, Amer.Eng. The verb meaning "to popularize by repetition" is from 1906. Slang verb sense "to put a bullet into" is recorded from 1870. Plug-ugly "ruffian" is first attested 1856, originally in Baltimore, from plug, Amer.Eng. slang for the stovepipe hats then popular among young men.
plum: O.E. plume, early Gmc. borrowing (cf. M.Du. prume, O.H.G. phruma, Ger. Pflaume) from V.L. *pruna, from L. prunum "plum," from Gk. prounon, later form of proumnon, from an Asiatic language. Change of pr- to pl- is unique to Gmc. Meaning "something desirable" is first recorded 1780, probably in ref. to the sugar-rich bits of a plum pudding, etc.