Online Etymology Dictionary

payee (n.): 1758, from pay (v.) + -ee.
payer (n.): "person who pays" (originally wages, late 14c., later taxes, early 15c.), from Old French paiere (13c.), agent noun from paier (see pay (v.)).
payload (n.): also pay-load, 1917, from pay + load (n.). Originally the part of a truck's (later an aircraft's) load from which revenue is derived (passengers, cargo, mail); figurative sense of "bombs, etc. carried by a plane or missile" is from 1936.
payment (n.): late 14c., from Old French paiement (13c.), from paiier (see pay (v.)).
paynim (n.): mid-13c., "heathen lands," from Old French paienime, paienisme "heathen, pagan; Saracen lands or culture or faith," from Late Latin paganismus "heathendom" (Augustine), from paganus "heathen" (see pagan); mistaken meaning "a heathen person" (late 14c., also in Old French) is via phrases such as paynim lands.
payoff (n.): also pay-off, 1905, "winnings from gambling," from pay (v.) + off. Meaning "graft, bribes" first attested 1930. Phrase to pay off "be profitable" is first recorded 1937.
payola (n.): "graft" (especially to disc jockeys from record companies to play their music), 1938 (in a "Variety" headline), from pay off "bribery" (underworld slang from 1930) + ending from Victrola, etc. (see pianola). Compare also plugola (1959), from plug (n.) in the advertising sense.
payor (n.): 1817, agent noun in Latin form from pay (v.). Chiefly legalese.
payout (n.): 1904, from pay (v.) + out. Originally in reference to oil wells that produced enough to justify the expense of drilling them.
Paypal (n.): e-commerce money transfer business, formed 2000 by merger of earlier firms.
payphone (n.): also pay-phone, 1906, from pay (v.) + phone (n.).
payroll (n.): 1740, from pay (v.) + roll (n.); "total amount paid to employees over a period," hence, via records-keeping, "list of employees receiving pay."
PBS: abbreviation of Public Broadcasting Service, 1970, America English. It succeeded National Educational Television (NET).
pcb: 1966, from polychlorinated biphenyl.
pcp: 1977, from phenocyclidine.
pda: by 1992, initialism (acronym) for personal digital assistant.
pdf: by 1992, initialism (acronym) for portable document format, a generic term.
PE: 1956 as an abbreviation of physical education (see physical).
pea (n.): early or mid-17c., false singular from Middle English pease (plural pesen), which was both single and collective (as with wheat, corn) but the "s" sound was mistaken for the plural inflection. From Old English pise (West Saxon), piose (Mercian) "pea," from Late Latin pisa, variant of Latin pisum "pea," from Greek pison "the pea," perhaps of Thracian or Phrygian origin [Klein].

In Southern U.S. and the Caribbean, used of other legumes as well. Pea soup is first recorded 1711 (pease-soup); applied to London fogs since at least 1849. Pea-shooter attested from 1803.
pea jacket (n.): 1721, loan-translation of North Frisian pijekkat, from Dutch pijjekker, from pij "coarse woolen cloth" + jekker "jacket." Middle English had pee "coat of coarse, thick wool" (late 15c.). Related: Pea-coat.
peace (n.): mid-12c., "freedom from civil disorder," from Anglo-French pes, Old French pais "peace, reconciliation, silence, permission" (11c., Modern French paix), from Latin pacem (nominative pax) "compact, agreement, treaty of peace, tranquility, absence of war" (source of Provençal patz, Spanish paz, Italian pace), from PIE *pag-/*pak- "fasten," related to pacisci "to covenant or agree" (see pact).

Replaced Old English frið, also sibb, which also meant "happiness." Modern spelling is 1500s, reflecting vowel shift. Sense in peace of mind is from c. 1200. Used in various greetings from c. 1300, from Biblical Latin pax, Greek eirene, which were used by translators to render Hebrew shalom, properly "safety, welfare, prosperity."

Sense of "quiet" is attested by 1300; meaning "absence or cessation of war or hostility" is attested from c. 1300. As a type of hybrid tea rose (developed 1939 in France by François Meilland), so called from 1944. Native American peace pipe is first recorded 1760. Peace-officer attested from 1714. Peace offering is from 1530s. Phrase peace with honor first recorded 1607 (in "Coriolanus"). The U.S. Peace Corps was set up March 1, 1962. Peace sign, both the hand gesture and the graphic, attested from 1968.
peace-keeping (n.): also peacekeeping, 1961 in the international sense, from peace + keeping, verbal noun from keep (v.). Earlier "preservation of law and order" (mid-15c.), from verbal phrase keep the peace. Related: Peace-keeper (1570s).
peaceable (adj.): early 14c., from Old French paisible "peaceful" (12c.), from pais (see peace). Related: Peacably.
peaceful (adj.): early 14c., "inclined to peace, friendly, pacific," from peace + -ful. Meaning "tranquil, calm, full of peace" is from mid-14c. In reference to nonviolent methods of effecting social change, it is attested from 1876. Related: Peacefully; peacefulness. Peaceful coexistence (1920) originally was in regard to Soviet policy toward the capitalist West.
peacemaker (n.): early 15c., from peace + maker.
peacenik (n.): 1962, from peace + -nik. An earlier equivalent was peacemonger (1808).
peacetime (n.): also peace-time, 1550s, from peace + time (n.).
peach (n.): c. 1400 (late 12c. as a surname), from Old French pesche "peach, peach tree" (Old North French peske, Modern French pêche), and directly from Medieval Latin pesca, from Late Latin pessica, variant of persica "peach, peach tree," from Latin malum Persicum, literally "Persian apple," translating Greek Persikon malon, from Persis "Persia" (see Persian).

In ancient Greek Persikos could mean "Persian" or "the peach." The tree is native to China, but reached Europe via Persia. By 1663 William Penn observed peaches in cultivation on American plantations. Meaning "attractive woman" is attested from 1754; that of "good person" is from 1904. Peaches and cream in reference to a type of complexion is from 1901. Peach blossom as a color is from 1702. Georgia has been the Peach State since 1939.
peach (v.): "to inform against," 1560s (earlier "to accuse, indict, bring to trial," mid-15c.), a shortening of appeach, an obsolete variant of impeach. Related: Peached; peaching.
peachy (adj.): 1590s, "resembling a peach" in some way, from peach (n.) + -y (2). Slang sense of "attractive" attested by 1900. Extended form peachy-keen recorded from 1953. Related: Peachiness.
peacock (n.): c. 1300, poucock, from Middle English po "peacock" + coc (see cock (n.)).

Po is from Old English pawa "peafowl" (cock or hen), from Latin pavo (genitive pavonis), which, with Greek taos said to be ultimately from Tamil tokei (but perhaps is imitative; Latin represented the peacock's sound as paupulo).

The Latin word also is the source of Old High German pfawo, German Pfau, Dutch pauw, Old Church Slavonic pavu. Used as the type of a vainglorious person from late 14c. Its flesh superstitiously was believed to be incorruptible (even St. Augustine credits this). "When he sees his feet, he screams wildly, thinking that they are not in keeping with the rest of his body." [Epiphanus]
peahen (n.): c. 1400, from Old English pawa "peafowl" (see peacock) + hen.
peak (n.): "pointed top," 1520s, variant of pike (n.4) "sharp point." Meaning "top of a mountain" first recorded 1630s, though pike was used in this sense c. 1400. Figurative sense is 1784. Meaning "point formed by hair on the forehead" is from 1833. According to OED, The Peak in Derbyshire is older than the word for "mountaintop;" compare Old English Peaclond, for the district, Pecsaetan, for the people who settled there, Peaces ærs for Peak Cavern; sometimes said to be a reference to an elf-denizen Peac "Puck."
peak (v.): 1570s, "to rise in a peak," from peak (n.). Figurative meaning "reach highest point" first recorded 1958. Related: peaked; peaking.
peaked (adj.): "sickly-looking," 1835, from past participle of obsolete verb peak "look sickly or thin, shrink, waste away" (1540s), which is perhaps from peak in sense of "become pointed" through emaciation. Related: Peakedness.
peal (n.): mid-14c., "a ringing of a bell" especially as a call to church service, generally considered a shortened form of appeal (n.), with the notion of a bell that "summons" people to church (compare similar evolution in peach (v.)). Extended sense of "loud ringing of bells" is first recorded 1510s.
peal (v.): 1630s, from peal (n.). Related: Pealed; pealing.
peanut (n.): 1807; see pea + nut. Earlier ground nut, ground pea (1769). The plant is native to South America; Portuguese traders took peanuts from Brazil and Peru to Africa by 1502 and it is known to have been cultivated in Chekiang Province in China by 1573, probably arriving with Portuguese sailors who made stops in Brazil en route to the Orient. Peanut butter attested by 1892; peanut brittle is from 1894. Peanut gallery "topmost rows of a theater" is from 1874, American English; peanuts "trivial sum" is from 1934.
pear (n.): Old English pere, peru "pear," common West Germanic (Middle Dutch, Middle Low German pere, Old High German pira, bira, Dutch peer), from Vulgar Latin *pera, variant of Latin pira, plural (taken for fem. singular) of pirum "pear," a loan word from an unknown source. It likely shares an origin with Greek apion "pear," apios "pear tree."
pearl (n.): mid-13c., from Old French perle (13c.) and directly from Medieval Latin perla (mid-13c.), of unknown origin. Perhaps from Vulgar Latin *pernula, diminutive of Latin perna, which in Sicily meant "pearl," earlier "sea-mussel," literally "ham, haunch, gammon," so called for the shape of the mollusk shells.

Other theories connect it with the root of pear, also somehow based on shape, or Latin pilula "globule," with dissimilation. The usual Latin word for "pearl" was margarita (see margarite).

For pearls before swine, see swine. Pearl Harbor translates Hawaiian Wai Momi, literally "pearl waters," so named for the pearl oysters found there; transferred sense of "effective sudden attack" is attested from 1942 (in reference to Dec. 7, 1941).
pearly (adj.): early 15c., from pearl + -y (2). Related: Pearliness. The pearly gates of Heaven (or the New Jerusalem) are attested by 1708, from Rev. 21:21.
peart (adj.): variant of pert (q.v.).
peasant (n.): early 15c., from Anglo-French paisant (mid-14c.), Old French paisent "local inhabitant" (12c., Modern French paysan), earlier paisenc, from pais "country, region" + Frankish suffix -enc "-ing."

Pais is from Late Latin pagensis "(inhabitant) of the district," from Latin pagus "country or rural district" (see pagan). As a style of garment in fashion (such as peasant blouse) from 1953.
peasantry (n.): 1550s, from peasant + -ry.
pease: Old English; see pea, of which this is the etymologically correct form.
peat (n.): c. 1200, in Scottish Latin, of unknown origin, probably from a Celtic root *pett- (source also of Cornish peyth, Welsh peth "quantity, part, thing," Old Irish pet, Breton pez "piece"). The earliest sense is not of the turf but of the cut piece of it, and the Celtic root may be connected to that of piece.
peaty (adj.): 1765, from peat + -y (2). Related: Peatiness.
peavey (n.): "pointed cant hook," a lumbering hook, 1878, said to be named for a John Peavey, blacksmith in Bolivar, N.Y., who supposedly invented it c. 1872. Other sources ascribe it to a Joseph Peavey of Stillwater, Maine, and give a date of 1858.
pebble (n.): small, smooth stone, late 13c., from Old English papolstan "pebblestone," of unknown origin. Perhaps imitative. Some sources compare Latin papula "pustule, pimple, swelling."
pecan (n.): 1712, paccan "the pecan tree," or a related hickory, from French pacane, from an Algonquian word meaning "nut" (compare Cree pakan "hard-shelled nut," Ojibwa bagaan, Abenaki pagann, Fox /paka:ni/).