Online Etymology Dictionary

postdate (v.): also post-date, 1620s, from post- + date (v.1) "to assign a date to, to mark a date on." Related: Postdated; postdating. Intransitive meaning "be of an earlier date" is from 1909.
postdiluvial (adj.): also post-diluvial, 1823, from post- + diluvial. Earlier was postdiluvian (1670s).
posted (adj.): "supplied with news," 1828, American English, past participle adjective from post (v.2).
poster (n.): "bill, placard, thing posted," 1838, from post (v.1). Poster boy/girl/child "someone given prominence in certain causes" is attested by 1990, in reference to fund-raising drives for charities associated with disability, featuring child sufferers, a feature since 1930s.
posterior (adj.): 1530s, "later," from Latin posterior "after, later, behind," comparative of posterus "coming after, subsequent," from post "after" (see post-). Meaning "situated behind" is from 1630s.
posterior (n.): "buttocks," euphemistic, 1610s, from posterior (adj.). Earlier it meant "those who come after, posterity" (1530s). Cf. Lithuanian pasturas "the last, the hindmost," from pas "at, by."
posteriority (n.): late 14c., "state of being behind," from Old French posteriorite (Modern French postériorité), from Medieval Latin posterioritatem (nominative posterioritas), from Latin posterior "later" (see posterior (adj.)).
posterity (n.): late 14c., from Old French posterité (14c.), from Latin posteritatem (nominative posteritas) "future, future time; after-generation, offspring;" literally "the condition of coming after," from posterus "coming after, subsequent," from post "after" (see post-). Old English words for this included æftercneoreso, framcynn.
postern (n.): late 13c., "back door, private door," from Old French posterne "side or rear gate," earlier posterle, from Late Latin posterula "small back door or gate," diminutive of Latin posterus "that is behind, coming after, subsequent," from post "after" (see post-).
posthaste (adv.): 1590s, from a noun (1530s) meaning "great speed," usually said to be from "post haste" instruction formerly written on letters (attested from 1530s), from post (adv.) + haste (n.). The verb post "to ride or travel with great speed" is recorded from 1550s.
posthumous (adj.): mid-15c., "born after the death of the originator" (author or father), from Late Latin posthumus, from Latin postumus "last, last-born," superlative of posterus "coming after, subsequent" (see posterior). Altered in Late Latin by association with Latin humare "to bury," suggesting death; the one born after the father's death obviously being the last. An Old English word for this was æfterboren, literally "after-born." Related: Posthumously.
postillon (n.): 1590s, from Middle French postillon (1530s), from Italian postiglione "forerunner, guide," especially for one carrying mail on horseback, from posta "mail" (see post (n.3)) + compound suffix from Latin -ilio.
postlude (n.): 1821, from post- + ending abstracted from prelude.
postman (n.): 1520s, from post (n.3) + man (n.).
postmark (n.): 1670s, from post (n.3) + mark (n.1). As a verb from 1716. Related: Postmarked; postmarking.
postmaster (n.): 1510s, from post (n.3) + master (n.).
postmodernism (n.): also post-modernism, by 1977, from post- + modernism. Defined by Terry Eagleton as "the contemporary movement of thought which rejects ... the possibility of objective knowledge" and is therefore "skeptical of truth, unity, and progress" ["After Theory," 2003]. Related: post-modernist (1965).
postnatal (adj.): 1831, from post- + natal.
postpone (v.): c.1500, from Latin postponere "put after; esteem less; neglect; postpone," from post "after" (see post-) + ponere "put, place" (see position (n.)). Related: Postponed; postponing.
postponement (n.): 1770, from postpone + -ment.
postposition (n.): "act of placing after, 1630s, from post- + position (n.). Related: Postpositional.
postprandial (adj.): also post-prandial, 1820, from post- "after" + Latin prandium "luncheon" (usually bread, fish, or cold meat, taken around noon), from *pram "early" (from PIE *pre-, variant of root per- (1) "forward, through;" see per) + edere "to eat" (see edible) + -al (1).
postscript (n.): 1550s, from Latin post scriptum "written after," from neuter past participle of Latin postscribere "write after," from post "after" (see post-) + scribere "to write" (see script).
postulant (n.): 1759, from French postulant "applicant, candidate," literally "one who asks," from Latin postulantem (nominative postulans), present participle of postulare "to ask, demand" (see postulate (v.)).
postulate (v.): 1530s, "nominate to a church office," from Medieval Latin postulatus, past participle of postulare "to ask, demand; claim; require," probably formed from past participle of Latin poscere "ask urgently, demand," from *posk-to-, Italic inchoative of PIE root *prek- "to ask questions" (cf. Sanskrit prcchati, Avestan peresaiti "interrogates," Old High German forskon, German forschen "to search, inquire"). Use in logic dates from 1640s, borrowed from Medieval Latin.
postulate (n.): 1580s, "a request, demand," from Latin postulatum "demand, request," properly "that which is requested," noun use of neuter past participle of postulare (see postulate (v.)). The sense in logic of "self-evident proposition" is from 1640s. The earlier noun in English was postulation (c.1400).
posture (n.): c.1600, from French posture (16c.), from Italian postura "position, posture," from Latin positura "position, station," from postulus, past participle of ponere "put, place" (see position (n.)).
posture (v.): 1620s, literal, from posture (n.). The figurative sense of "take up an artificial mental position" is attested from 1877. Related: Postured; posturing.
Posturpedic (n.): trademark name (Sealy, Inc., Chicago, U.S.A.) for a brand of mattress, filed in 1951; from posture (n.) + second element from orthopedic.
postwar (adj.): also post-war, 1906, in reference to the U.S. Civil War, a hybrid from post- + war (n.). Cf. post-bellum.
posy (n.): also posey, 1530s, "line of verse engraved on the inner surface of a ring," from poesy "poetry; a passage of poetry," which is recorded in this sense from early 15c. Meaning "flower, bouquet" first recorded 1570s, from notion of the language of flowers.
pot (n.1): "vessel," from late Old English pott and Old French pot "pot, container, mortar" (also in erotic senses), both from a general Low Germanic (cf. Old Frisian pott, Middle Dutch pot) and Romanic word from Vulgar Latin *pottus, of uncertain origin, said by Barnhart and OED to be unconnected to Late Latin potus "drinking cup." Celtic forms are said to be borrowed from English and French.

Slang meaning "large sum of money staked on a bet" is attested from 1823. Pot roast is from 1881; phrase go to pot (16c.) suggests cooking. In phrases, the pot calls the kettle black-arse is from c.1700; shit or get off the pot is traced by Partridge to Canadian armed forces in World War II.
pot (n.2): "marijuana," 1938, probably a shortened form of Mexican Spanish potiguaya "marijuana leaves."
pot (v.): "to put in a pot," 1610s, from pot (n.1). Related: Potted; potting. Earlier it meant "to drink from a pot" (1590s).
pot-bellied (adj.): also potbellied, 1650s, from pot (n.1) + bellied. As a type of stove from 1973.
pot-belly (n.): 1714, from pot (n.1) + belly (n.). Pot-belly stove, so called for its shape, attested from 1943.
pot-holder (n.): also potholder, the cloth variety so called by 1902, from pot (n.1) + holder.
pot-pie (n.): also potpie, 1823, American English, from pot (n.1) + pie (n.).
potable (adj.): early 15c., from Old French potable (14c.) and directly from Late Latin potabilis "drinkable," from Latin potare "to drink" (see potion).
potage (n.): "thick soup," 1560s, from French potage "soup, broth" (see pottage, which is an earlier English borrowing of the same French word).
potamo-: word-forming element meaning "river," from comb. form of Greek potamos "river," perhaps literally "rushing water," from PIE *pet- "to rush, to fly" (see petition).
potamology (n.): "the study of rivers," 1829, from potamo- + -logy.
potash (n.): 1751, earlier -pot-ashes (1640s), a loan-translation of older Dutch potaschen, literally "pot ashes" (16c.); so called because it was originally obtained by soaking wood ashes in water and evaporating the mixture in an iron pot. Cf. German Pottasche, Danish potaske, Swedish pottaska, all also from Dutch. See also potassium. French potasse (1570s), Italian potassa are Germanic loan-words. The original plural was pot-ashes.
potassium (n.): metallic element, 1807, coined by English chemist Sir Humphrey Davy (1778-1829) from Modern Latin potassa, Latinized form of potash (q.v.). Davy first isolated it from potash. Symbol K is from Latin kalium "potash," from Arabic al-qaliy "the ashes, burnt ashes" (see alkali).
potation (n.): early 15c., from Old French potacion, from Latin potationem (nom. potatio) "a drinking; poisonous drink, potion," noun of action from past participle stem of potare "to drink" (see potion).
potato (n.): 1560s, from Spanish patata, from a Carib language of Haiti batata "sweet potato." Sweet potatoes were first to be introduced to Europe; in cultivation in Spain by mid-16c.; in Virginia by 1648. Early 16c. Portuguese traders carried the crop to all their shipping ports and the sweet potato was quickly adopted from Africa to India and Java.

The name later (1590s) was extended to the common white potato, from Peru, which was at first (mistakenly) called Virginia potato, or, because at first it was of minor importance compared to the sweet potato, bastard potato. Spanish invaders in Peru began to use white potatoes as cheap food for sailors 1530s. The first potato from South America reached Pope Paul III in 1540; grown in France at first as an ornamental plant. According to popular tradition, introduced to Ireland 1565 by John Hawkins. Brought to England from Colombia by Sir Thomas Herriot, 1586.

German kartoffel (17c.) is a dissimilation from tartoffel, ultimately from Italian tartufolo (Vulgar Latin *territuberem), originally "truffle." Frederick II forced its cultivation on Prussian peasants in 1743. The French is pomme de terre, literally "earth-apple;" a Swedish dialectal word for "potato" is jordpäron, literally "earth-pear."

Colloquial pronunciation tater is attested in print from 1759. Potato chip (n.) attested from 1879. To drop (something) like a hot potato is from 1824. Children's counting-out rhyme that begins one potato, two potato first recorded 1885 in Canada. Slang potato trap "mouth" attested from 1785.
potboiler (n.): also pot-boiler, 1864 in the figurative literary sense, from pot (n.1) + agent noun from boil (v.). The notion is of something one writes solely to put food on the table.
poteen (n.): "illicit whiskey," 1812, from Irish poitin "little pot," suggesting distillation in small quantities, from English pot (n.1) "vessel" + diminutive suffix -in, -een.
Potemkin: in reference to Grigory Aleksandrovich Potemkin (1739-1791), favorite of Catherine II of Russia, especially in reference to the sham villages supposedly erected under his orders for the empress’ tour of Crimea (1787) to create an impression of prosperity and progress. The silent film "Battleship Potemkin" dates from 1925, depicting (with elaboration) events of 1905 and the mutiny of a Russian battleship named for the Tsarist minister.
potence (n.): "potency," early 15c., from Old French potence "power," from Latin potentia (see potent).