Online Etymology Dictionary

pianist (n.): 1822, from French pianiste, from Italian pianista; see piano + -ist. Earlier in English in the French form, pianiste (1816).
piano (n.): 1803, from French piano (18c.), Italian piano, shortened forms of pianoforte (q.v.). As an adverb, "softly," in musical directions (superlative pianissimo), attested from 1680s. Piano wire attested from 1831.
pianoforte (n.): 1767, from Italian, from piano e forte "soft and loud," in full, gravicembalo col piano e forte "harpsichord with soft and loud" (c.1710), said to have been so named by inventor Bartolomeo Cristofori (1655-1731) of Padua because the ability via dampers to vary the tone is one of the main changes from the harpsichord. Italian piano (adj.) ultimately is from Latin planus "flat, smooth, even," later "soft" (see plane (n.1)).
pianola (n.): c.1896, trademark name (1901) of a player piano, from piano, the ending perhaps abstracted from viola and meant as a diminutive suffix. The pianola's popularity led to a rash of product names ending in -ola, especially Victrola (q.v.), and slang words such as payola.
piaster (n.): also piastre, 1620s, "Spanish dollar, piece of eight," also used as the name of a monetary unit and coin of Turkey (1610s, in Turkish called ghurush, but originally debased Spanish dollars), from French piastre, from Italian piastra "thin metal plate," short for impiastro "plaster," from Latin emplastrum, from Greek emplastron (see plaster). The Italian word was applied to the Spanish silver peso, later to the Turkish coin based on it. Cf. shinplaster.
piazza (n.): 1580s, "public square in an Italian town," from Italian piazza, from Latin platea "courtyard, broad street," from Greek plateia (hodos) "broad (street);" see place (n.). According to OED, mistakenly applied in English 1640s to the colonnade of Covent Garden, designed by Inigo Jones, rather than to the marketplace itself; hence "the verandah of a house" (1724, chiefly American English).
pibroch (n.): kind of bagpipe music, 1719, from Gaelic piobaireachd, literally "piper's art," from piobair "a piper" (from piob "pipe," an English loan word; see pipe (n.1)) + -achd, suffix denoting function.
pic (n.): 1884 as a shortening of picture (n.). Short for motion picture from 1936. Colloquial piccy is recorded from 1889.
pica (n.1): "size of type of about six lines to the inch" (12 point), 1580s, probably from pica, name of a book of rules in Church of England for determining holy days (late 15c. in Anglo-Latin), probably from Latin pica "magpie" (see pie (n.2)); the book so called perhaps from the color and the "pied" look of the old type on close-printed pages. The type size was that generally used to print ordinals.
pica (n.2): "pathological craving for substance unfit for food" (such as chalk), 1560s, from Medieval Latin pica "magpie" (see pie (n.2)), probably translating Greek kissa, kitta "magpie, jay," also "false appetite." The connecting notion may be the birds' indiscriminate feeding.
picador (n.): 1797, from Spanish picador, literally "pricker," from picar "to pierce," from Vulgar Latin *piccare "to pierce" (see pike (n.2)). He pricks the bull with a lance to provoke it.
Picardy: from Old French pic (Modern French pique) "pike" (see pike (n.2)); the characteristic weapon of the people who lived in this part of northern France in ancient times.
picaresque (adj.): 1810, from Spanish picaresco "roguish," from picaro "rogue," of uncertain origin, possibly from picar "to pierce," from Vulgar Latin *piccare (see pike (n.2)). Originally in roman picaresque "rogue novel," the classic example being "Gil Blas."
picaroon (n.): 1620s, "rogue, thief, adventurer; pirate, sea-robber; small pirate ship," from Spanish picaron, augmentative of picaro "rogue" (see picaresque); also cf. -oon.
picayune (n.): 1804, "coin of small value," probably from Louisiana French picaillon "coin worth 5 cents," earlier the French name of an old copper coin of Savoy (1750), from Provençal picaioun "small copper coin," from picaio "money," of uncertain origin. Adjectival figurative sense of "paltry, mean" recorded from 1813.
piccalilli (n.): "pickle of chopped vegetables," 1769, piccalillo, perhaps a fanciful elaboration of pickle. Spelling with an -i attested from 1845.
piccaninny (n.): also pickaninny, 1650s, from West Indies patois, formed as a diminutive from Spanish pequeño or Portuguese pequeno "little, small," of uncertain origin, related to French petit (see petit (adj.)). As late as 1836 applied affectionately to any small child or baby, regardless of race.
piccolo (n.): 1856, piccolo flute, from French piccolo, from Italian flauto piccolo "small flute," from piccolo "small," perhaps a children's made-up word, or from picca "point," or from Vulgar Latin root *pikk- "little," related to *piccare "to pierce" (see pike (n.2)). Other sources suggest it is from the same source as French petit (see petit (adj.)).
pick (v.): early 13c., picken "to peck;" c.1300, piken "to work with a pick," probably representing a fusion of Old English *pician "to prick," (implied by picung "a piercing, pricking," an 8c. gloss on Latin stigmata) with Old Norse pikka "to prick, peck," from a common Germanic root (cf. Middle Dutch picken, German picken "to pick, peck"), perhaps imitative. Influence from Middle French piquer "to prick, sting" (see pike (n.2)) also is possible, but that French word generally is not considered a source of the English word. Related: Picked; picking.

Meaning "to eat with small bites" is from 1580s. The meaning "to choose, select, pick out" emerged late 14c., from earlier meaning "to pluck with the fingers" (early 14c.). Sense of "to rob, plunder" (c.1300) weakened to a milder sense of "steal petty things" by late 14c. Of forcing locks with a pointed tool, by 1540s. Meaning "to pluck (a banjo)" is recorded from 1860. To pick a quarrel, etc. is from mid-15c.; to pick at "find fault with" is from 1670s. Pick on "single out for adverse attention" is from late 14c.; pick off "shoot one by one" is recorded from 1810; baseball sense of "to put out a runner on base" is from 1939. Also cf. pick up. To pick and choose "select carefully" is from 1660s (choose and pick is attested from c.1400).
pick (n.1): c.1200, "pointed tool for breaking up rock or ground," variant of pike (n.4). Meaning "sharp tool" is from mid-14c.
pick (n.2): mid-15c., "a blow with a pointed instrument," from pick (v.). Meaning "plectrum for a guitar, lute, etc." is from 1895; as a type of basketball block, from 1951; meaning "choicest part or example" is first recorded 1760.
pick up (v.): early 14c. as a verbal phrase, "lift and take," from pick (v.) + up (adv.). Of persons, "make acquaintance or take along," especially for sexual purposes, 1690s. Meaning "cause (someone) to revive" is from 1857. Sense of "tidy up" is from 1861; that of "arrest" is from 1871; meaning "gain speed" is from 1922; meaning "to pay" (a check, tab, etc.) is from 1945. Pick-me-up "stimulating alcoholic drink" is attested from 1867.
pickaxe (n.): also pick-axe, early 15c., folk etymology alteration (by influence of axe) of Middle English picas (mid-13c.), via Anglo-French piceis, Old French pocois (11c.) and directly from Medieval Latin picosa "pick," related to Latin picus "woodpecker" (see pie (n.2)).
picked (adj.): "chosen for excellence," 1540s, past participle adjective from pick (v.).
pickelhaube (n.): Prussian spiked helmet, 1875, from German Pickelhaube, from pickel "(ice)pick, pickaxe," + haube "hood, bonnet." But the German word is attested 17c., long before the helmet type came into use, and originally meant simply "helmet;" Palmer reports a German theory (Andresen) that it is a folk-etymology: "as if from Pickel and haube, a cap or coif[;] more correctly written Biekelhaube, [it] is for Beckelhaube, a word most probably derived from becken, a basin."
picker (n.): 1520s, "one who steals;" literal use "one who picks" is from 1660s; agent noun from pick (v.). From 1923 as "one who plays the banjo." Picker-upper attested from 1936.
pickerel (n.): "young pike," late 13c., diminutive of pike, the fish (see pike (n.3)), with French pejorative suffix -rel; perhaps formed in Anglo-French.
picket (n.): 1680s, "pointed stake (for defense against cavalry, etc.)," from French piquet "pointed stake," from piquer "to pierce" (see pike (n.2)). Sense of "troops posted to watch for enemy" first recorded 1761; that of "striking workers stationed to prevent others from entering a factory" is from 1867. Picket line is 1856 in the military sense, 1945 of labor strikes.
picket (v.): 1745, "to enclose with pickets," from picket (n.). The sense in labor strikes, protests, etc., is attested from 1867. Related: Picketed; picketing.
pickle (n.): c.1400, probably from Middle Dutch pekel "pickle, brine," or related words in Low German and East Frisian (cf. Dutch pekel, East Frisian päkel, German pökel), of uncertain origin or original meaning. Klein suggests the name of a medieval Dutch fisherman who developed the process. Originally a sauce served with meat or fowl; meaning "cucumber preserved in pickle" first recorded 1707, via use of the word for the salty liquid in which meat, etc. was preserved (c.1500). Figurative sense of "sorry plight" first recorded 1560s, from the time when the word still meant a sauce served on meat about to be eaten. Meaning "troublesome boy" is from 1788, perhaps from the notion of being "imbued" with roguery.
pickle (v.): 1550s, from pickle (n.). Related: Pickled; pickling.
pickled (adj.): "drunk," American English slang, 1900, figurative past participle adjective from pickle (v.).
picklock (n.): 1550s, from pick (v.) + lock (n.).
pickpocket (n.): also pick-pocket, 1590s, from pick (v.) + pocket (n.). Earlier was pick-purse (late 14c.). As a verb from 1670s.
pickup (n.): also pick-up, "that which is picked up," 1848; see pick up (v.). As "act of picking up" from 1882. Meaning "capacity for acceleration" is from 1909; that of "recovery" is from 1916. In reference to a game between informal teams chosen on the spot, from 1905 (as an adjective in this sense by 1936).

Meaning "small truck used for light loads," 1937, is shortened from pickup truck (pickup body is attested from 1928). The notion probably being of a vehicle for use to "pick up" (feed, lumber, etc.) and deliver it where it was needed.
picky (adj.): 1867, from pick (v.) + -y (2). Related: Pickiness. The earliest recorded uses are in reference to eating.
picnic (n.): 1748 (in Chesterfield's "Letters"), but rare before c.1800 as an English institution; originally a fashionable pot-luck social affair, not necessarily out of doors; from French piquenique (1690s), perhaps a reduplication of piquer "to pick, peck," from Old French (see pike (n.2)), or the second element may be nique "worthless thing," from a Germanic source. Figurative sense of "something easy" is from 1886. Picnic table recorded from 1926, originally a folding table.
picnic (v.): "go on a picnic," 1842, from picnic (n.). Related: Picnicked; picnicking. The -k- is inserted to preserve the "k" sound of -c- before a suffix beginning in -i-, -y-, or -e- (cf. traffic/trafficking, panic/panicky, shellac/shellacked).
pico-: word-forming element used in making names for very small unites of measure, 1915 (formally adopted c.1952 as a scientific prefix meaning "one trillionth"), from Spanish pico "a little over, a small balance," literally "sharp point, beak," of Celtic origin (cf. Gaulish beccus "beak").
picosecond (n.): 1966, from pico- + second (n.).
Pict (n.): an ancient people of Great Britain, late 14c., from Late Latin Picti (late 3c., probably a nickname given them by Roman soldiers), usually taken as derived from picti "painted," but probably ultimately from the Celtic name of the tribe, perhaps Pehta, Peihta, literally "the fighters" (cf. Gaulish Pictavi, a different people, who gave the name to the French city of Poitiers). They painted and tattooed themselves, which may have suggested a Roman folk-etymology alteration of the name. The Old English name for the people was Peohtas.
In Scottish folk-lore the Pechts are often represented as a dark pygmy race, or an underground people; and sometimes identified with elves, brownies, or fairies. [OED]
Related: Pictish; Pictland.
pictogram (n.): 1910, from stem of Latin pictus "painted," past participle of pingere "to paint" (see paint (v.)) + -gram.
pictograph (n.): "picture or symbol representing an idea," 1851, from Latin pictus "painted," past participle of pingere "to paint" (see paint (v.)) + -graph "something written," from Greek graphe "writing," from graphein "to write, express by written characters," earlier "to draw, represent by lines drawn" (see -graphy). First used in reference to American Indian writing. Related: Pictography.
pictorial (adj.): 1640s, from Latin pictorius "of a painter," from pictor "painter," from past participle stem of pingere "to make pictures" (see paint (v.)) + -al (1). The noun meaning "journal in which pictures are the main feature" is first recorded 1844. Related: Pictorially.
picturable (adj.): 1796, from picture (v.) + -able. Related: Picturably.
picture (n.): early 15c., "drawing, painting," from Latin pictura "painting," from pictus, past participle of pingere "to make pictures, to paint, to embroider," (see paint (v.)). Picture window is from 1938. Picture post-card first recorded 1899. Phrase every picture tells a story first attested 1900, in advertisements for an illustrated life of Christ. To be in (or out of) the picture in the figurative sense dates to 1900.

Expression a picture is worth a thousand words, attested from 1918, probably was from the publication trade (the notion that a picture was worth 1,000 words is in printers' publications by 1911). The phrase also was in use in the form worth a million words, the form used by American newspaper editor Arthur Brisbane (1864-1936) in an editorial much-read c.1916 titled "What is a Good Newspaper" in the "New York Evening Journal." In part it read, "After news and humor come good pictures. In this day of hurry we learn through the eye, and one picture may be worth a million words." It seems to have emerged into general use via the medium of advertising (which scaled down the number and also gave the expression its spurious origin story as "a Japanese proverb" or some such thing, by 1919). Earlier various acts or deeds (and in one case "the arrow") were said to be worth a thousand words.
picture (v.): late 15c. in the literal sense; 1738 in the mental sense, from picture (n.). Related: Pictured; picturing.
picturephone (n.): 1964, from picture (n.) + phone (n.1).
pictures (n.): "movies," 1912, short for moving pictures.
picturesque (adj.): 1703, on pattern of French pittoresque, a loan-word from Italian pittoresco, literally "pictorial" (1660s), from pittore "painter," from Latin pictorem (nominative pictor); see painter (n.1). As a noun from 1749. Related: Picturesquely; picturesqueness.