Online Etymology Dictionary

phthisis (n.): 1520s, from Late Latin phthisis "consumption," from Greek phthisis "wasting, consumption; perishing, decay; waxing," from phthiein "to decay, waste away," from PIE root *dhgwhei- "to perish, die away" (source also of Sanskrit ksitih "destruction," ksinati "perishes").
phyco-: word-forming element in science meaning "seaweed, algae," from Latinized comb. form of Greek phykos "seaweed, sea wrack."
phycology (n.): "study of seaweeds," 1847, from phyco- + -logy. Related: Phycological; phycologist.
phylactery (n.): late 14c., "small leathern box containing four Old Testament texts," from Old French filatiere (12c.) and directly from Medieval Latin philaterium, from Late Latin phylacterium "reliquary," from Greek phylacterion "safeguard, amulet," noun use of neuter of adjective phylakterios "serving as a protection," from phylakter "watcher, guard," from phylassein "to guard or ward off," from phylax (genitive phylakos) "guard," of unknown origin. Sometimes worn on the forehead, based on a literal reading of scripture:
Ye shall bind them [my words] for a sign upon your hands, and they shall be for frontlets between your eyes. [Deut. xi:18]
phyletic (adj.): "racial, pertaining to race," 1873, probably coined in German from Greek phyletikos "of one's tribe," from phyletes "fellow tribesman," from phyle (see phylo-).
Phyllis: fem. proper name, generic proper name for a comely rustic maiden in pastoral poetry (1630s), from Latin Phyllis, a girl's name in Virgil, Horace, etc., from Greek Phyllis, female name, literally "foliage of a tree," from phyllon leaf," from PIE *bholyo- "leaf," from root *bhel- (3) "to thrive, bloom," possibly identical with *bhel- (2) "to blow, inflate, swell" (see bole). In English, often spelled Phillis, probably from influence of phil- "loving." Her sweetheart usually was Philander.
phyllo-: before vowels phyll-, word-forming element meaning "leaf," from Greek phyllo-, comb. form of phyllon "leaf," from PIE *bhol-yo- "leaf," suffixed form of root *bhel- (3) "to thrive, bloom" (see folio).
phyllophagous (adj.): "leaf-eating," 1819, from phyllo- + -phagous.
phylo-: before vowels phyl-, word-forming element from comb. form of Greek phylon, phyle "a tribe," also "a political subdivision in ancient Athens," from base of phyein "to bring forth, produce, make to grow," whence also physis "nature" (see physic).
phylogenesis (n.): 1870, coined in German by Haeckel, from phylo- + -genesis "birth, origin, creation."
phylogeny (n.): "genesis and evolution of a phylum," 1869, from German Phylogenie, coined 1866 by German biologist Ernst Heinrich Haeckel (1834-1919) from Greek phylon "race" (see phylo-) + -geneia "origin," from -genes "born" (see genus). Related: Phylogenic.
phylum (n.): "division of the plant or animal kingdom," 1868, Modern Latin, coined by French naturalist Georges Léopole Chrétien Frédéric Dagobert, Baron Cuvier (1769-1832) from Greek phylon "race, stock," related to phyle "tribe, clan" (see physic). The immediate source of the English word probably is from German.
physic (n.): c. 1300, fysike, "art of healing, medical science," also "natural science" (c. 1300), from Old French fisike "natural science, art of healing" (12c.) and directly from Latin physica (fem. singular of physicus) "study of nature," from Greek physike (episteme) "(knowledge) of nature," from fem. of physikos "pertaining to nature," from physis "nature," from phyein "to bring forth, produce, make to grow" (related to phyton "growth, plant," phyle "tribe, race," phyma "a growth, tumor") from PIE root *bheue- "to be, exist, grow" (see be). Spelling with ph- attested from late 14c. (see ph). As a noun, "medicine that acts as a laxative," 1610s. The verb meaning "to dose with medicine" is attested from late 14c.
physical (adj.): early 15c., "of or pertaining to material nature" (in medicine, opposed to surgical), from Medieval Latin physicalis "of nature, natural," from Latin physica "study of nature" (see physic). Meaning "pertaining to matter" is from 1590s; meaning "having to do with the body, corporeal" is attested from 1780. Meaning "characterized by bodily attributes or activities" is attested from 1970. Physical education first recorded 1838; abbreviated form phys ed is from 1955. Physical therapy is from 1922. Related: Physically.
physical (n.): "a physical examination," by 1934, from physical (adj.).
physicality (n.): 1590s, from physical + -ity.
physician (n.): early 13c., fisicien "a healer, a medical practitioner," from Old French fisiciien "physician, doctor, sage" (12c., Modern French physicien means "physicist"), from fisique "art of healing," from Latin physica "natural science" (see physic). Distinguished from surgeon from c. 1400. The ph- spelling attested from late 14c. (see ph).
physicist (n.): 1836, from physics + -ist. Coined by the Rev. William Whewell (1794-1866), English polymath, to denote a "cultivator of physics" as opposed to a physician.
As we cannot use physician for a cultivator of physics, I have called him a physicist. We need very much a name to describe a cultivator of science in general. I should incline to call him a Scientist. Thus we might say, that as an Artist is a Musician, Painter, or Poet, a Scientist is a Mathematician, Physicist, or Naturalist. [William Whewell, "The Philosophy of the Inductive Sciences," London, 1840]
physico-: word-forming element meaning "physical, physically; natural," from Latinized comb. form of Greek physikos "natural, physical" (see physic).
physicological (adj.): 1704, from physicologic "logic illustrated by physics," from physico- + logic. Related: Physicologically.
physics (n.): 1580s, "natural science," from physic in sense of "natural science." Also see -ics. Based on Latin physica (neuter plural), from Greek ta physika, literally "the natural things," name of Aristotle's treatise on nature. Specific sense of "science treating of properties of matter and energy" is from 1715.
physio-: word-forming element meaning "nature, natural, physical," from Greek physio-, comb. form of physios "nature" (see physic).
physiognomy (n.): late 14c., "art of judging characters from facial features," from Old French phizonomie and directly from Late Latin physiognomia, from Greek physiognomia "the judging of a person's nature by his features," from physio- (see physio-) + gnomon (genitive gnomonos) "judge, indicator" (see gnomon). Meaning "face, countenance, features" is from c. 1400. Related: Physiognomical.
physiological (adj.): c. 1600, "pertaining to natural science," from physiology + -ical. From 1814 as "pertaining to physiology." Related: Physiologically.
physiology (n.): 1560s, "study and description of natural objects," from Middle French physiologie or directly from Latin physiologia "natural science, study of nature," from Greek physiologia "natural science, inquiry into nature," from physio- "nature" (see physio-) + logia "study" (see -logy). Meaning "science of the normal function of living things" is attested from 1610s. Related: Physiologic; physiologist.
physiotherapy (n.): 1905, from physio- + therapy. Related: Physiotherapist.
physique (n.): 1826, from French physique, noun use of physique (adj.) "physical," from Latin physicus "natural, physics," from Greek physikos, from physis "nature" (see physic).
phyto-: word-forming element meaning "plant," from Greek phyton "plant," literally "that which has grown," from phyein "to grow" (see physic).
phytoplankton (n.): 1897, from phyto- + plankton.
pi (n.): Greek letter, from Hebrew, literally "little mouth." As the name of the mathematical constant, from 1841 in English, used in Latin 1748 by Swiss mathematician Leonhart Euler (1707-1783), as an abbreviation of Greek periphereia "periphery." For the meaning "printer's term for mixed type," see pie (3).
pianissimo (adv.): 1724, from Italian pianissimo "very softly," from Latin pianissimus, superlative of pianus (see piano).
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. Compare 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 see -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," both from a Germanic root (source also of 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 see pick up. To pick and choose "select carefully" is from 1660s (choose and pick is attested from c. 1400).