Online Etymology Dictionary

popsicle (n.): 1923, trademark name registered by Frank Epperson of Oakland, Calif., presumably from (lolly)pop + (ic)icle.
popster (n.): pop-culture enthusiast, 1963, from pop (adj.)+ -ster.
populace (n.): 1570s, from Middle French populace (16c.), from Italian popolaccio "riffraff, rabble," from popolo "people" (from Latin populus "people;" see people (n.)) + pejorative suffix -accio.
popular (adj.): early 15c., "public," from Middle French populier (Modern French populaire) and directly from Latin popularis "belonging to the people, general, common; devoted to or accepted by the people; democratic," from populus "people" (see people (n.)).

Meaning "suited to ordinary people" is from 1570s in English; hence, of prices, "low, affordable to average persons" (1859). Meaning "well-liked, admired by the people" is attested from c. 1600. Of art, entertainment, etc., "favored by people generally" from 1819 (popular song). Related: Popularly. Popular Front "coalition of Communists, Socialists, and radicals" is from 1936, first in a French context.
popularity (n.): "fact or condition of being beloved by the people," c. 1600, from French popularité (15c.), from popular + -ity. Classical Latin popularitas meant "fellow-citizenship." Popularity contest is from 1880.
popularization (n.): 1797, noun of action from popularize.
popularize (v.): "to make a complex topic intelligible to the people," 1833, from popular + -ize. Earlier "to cater to popular taste" (1590s); "to make popular" (1797). Related: Popularized; popularizing.
populate (v.): 1610s, from Medieval Latin populatus, past participle of populare "inhabit, to people," from Latin populus "inhabitants, people, nation" (see people (n.)). Related: Populated; populating.
population (n.): 1610s, from Late Latin populationem (nominative populatio) "a people; a multitude," as if from Latin populus "a people" (see people (n.)). Population explosion is first attested 1953.
populism (n.): 1893; see populist + -ism. Originally in reference to the political theories of the U.S. Populist Party (also People's Party).
populist: 1892 (n.) "adherent of populism;" 1893 (adj.), American English, from Latin populus "people" (see people (n.)) + -ist. Originally in reference to the U.S. Populist Party organized February 1892 to promote certain issues important to farmers and workers. The term outlasted the party, and by 1920s came to mean "representing the views of the masses" in a general way.
populous (adj.): early 15c., from post-classical Latin populosus "full of people, populous," from populus "people" (see people (n.)). Related: Populousness.
porcelain (n.): 1530s, from Middle French porcelaine and directly from Italian porcellana "porcelain" (13c.), literally "cowrie shell," the chinaware so called from resemblance of its lustrous transparency to the shiny surface of the shells. The shell's name in Italian is from porcella "young sow," fem. of Latin porcellus "young pig," diminutive of porculus "piglet," diminutive of porcus "pig" (see pork (n.)). According to an old theory, the connection of the shell and the pig is a perceived resemblance of the shell opening to the exposed outer genitalia of pigs.
porcelain is china & china is p.; there is no recondite difference between the two things, which indeed are not two, but one; & the difference between the two words is merely that china is the homely term, while porcelain is exotic & literary. [Fowler]
porch (n.): c. 1300, "covered entrance," from Old French porche "porch, vestibule," from Latin porticus "covered gallery, covered walk between columns, arcade, portico, porch," from porta "city gate, gate; door, entrance," from PIE root *per- (2) "to lead, pass over" (see port (n.1)). The Latin word was borrowed directly into Old English as portic.
porcine (adj.): early 15c., "pertaining to swine; swinish," from Old French porcin or directly from Latin porcinus "of a hog," from porcus "hog, pig" (see pork (n.)).
porcupine (n.): c. 1400, porke despyne, from Old French porc-espin (early 13c., Modern French porc-épic), literally "spiny pig," from Latin porcus "hog" + spina "thorn, spine" (see spine). The word had many forms in Middle English and early Modern English, including portepyn, porkpen, porkenpick, porpoynt, and Shakespeare's porpentine (in "Hamlet").
pore (v.): "gaze intently," early 13c., of unknown origin, with no obvious corresponding word in Old French. Perhaps from Old English *purian, suggested by spyrian "to investigate, examine," and spor "a trace, vestige." Related: Pored; poring.
pore (n.): "minute opening," late 14c., from Old French pore (14c.) and directly from Latin porus "a pore," from Greek poros "a pore," literally "passage, way," from PIE *por- "going, passage," from root *per- (2) "to lead, pass over" (see port (n.1)).
porgy (n.): name given to various sea fishes, 1725, probably from pargo "sea bream" (1550s), from Spanish or Portuguese pargo, from Latin phagrum (nom. phager), from Greek phagros "sea bream."
Porifera (n.): 1843, Modern Latin, literally "bearing pores," neuter plural of porifer, from Latin porus "pore, opening" (see pore (n.)) + -fer "bearing" (see infer). Related: Poriferal; poriferous.
pork (n.): c. 1300 (early 13c. in surname Porkuiller), "flesh of a pig as food," from Old French porc "pig, swine, boar," and directly from Latin porcus "pig, tame swine," from PIE *porko- "young swine" (source also of Umbrian purka; Old Church Slavonic prase "young pig;" Lithuanian parsas "pig;" and Old English fearh, Middle Dutch varken, both from Proto-Germanic *farhaz).

Pork barrel in the literal sense is from 1801, American English; meaning "state's financial resources (available for distribution)" is attested from 1907 (in full, national pork barrel); it was noted as an expression of U.S. President President William Howard Taft:
"Now there is a proposition that we issue $500,000,000 or $1,000,000,000 of bonds for a waterway, and then that we just apportion part to the Mississippi and part to the Atlantic, a part to the Missouri and a part to the Ohio. I am opposed to it. I am opposed to it because it not only smells of the pork barrel, but it will be the pork barrel itself. Let every project stand on its bottom." ["The Outlook," Nov. 6, 1909, quoting Taft]
The magazine article that includes the quote opens with:
We doubt whether any one knows how or when, or from what application of what story, the phrase "the National pork barrel" has come into use. If not a very elegant simile, it is at least an expressive one, and suggests a graphic picture of Congressmen eager for local advantage going, one after another, to the National pork barrel to take away their slices for home consumption.
Pork in this sense is attested from 1862 (compare figurative use of bacon). Pork chop is attested from 1858. Pork pie is from 1732; pork-pie hat (1855) originally described a woman's style popular c. 1855-65, so called for its shape.
porker (n.): 1650s, "young hog fattened for food," from pork (n.). Meaning "fat person" is from 1892.
porky (adj.): 1852, from pork (n.) + -y (2). Related: Porkiness.
porn (n.): 1962, abbreviation of pornography. Porno (adj.) is attested from 1952.
porno (adj.): 1952 (Norman Mailer), short for pornographic.
pornographer (n.): 1850, from pornography + -er (1).
pornographic (adj.): 1853, from pornography + -ic.
pornography (n.): 1843, "ancient obscene painting, especially in temples of Bacchus," from French pornographie, from Greek pornographos "(one) depicting prostitutes," from porne "prostitute," originally "bought, purchased" (with an original notion, probably of "female slave sold for prostitution"), related to pernanai "to sell," from PIE root *per- (5) "to traffic in, to sell" (see price (n.)) + graphein "to write" (see -graphy). A brothel in ancient Greek was a porneion.
Pornography, or obscene painting, which in the time of the Romans was practiced with the grossest license, prevailed especially at no particular period in Greece, but was apparently tolerated to a considerable extent at all times. Parrhasius, Aristides, Pausanias, Nicophanes, Chaerephanes, Arellius, and a few other [pornographoi] are mentioned as having made themselves notorious for this species of license. [Charles Anthon, "Dictionary of Greek and Roman Antiquities," New York, 1843]
In reference to modern works by 1859 (originally French novels), later as a charge against native literature; sense of "obscene pictures" in modern times is from 1906. Also sometimes used late 19c. for "description of prostitutes" as a matter of public hygiene. The "Medical Archives" in 1873 proposed porniatria for "the lengthy and really meaningless expression 'social evil hospital' ...."
I shall not today attempt further to define the kinds of material I understand to be embraced within that shorthand description [hard-core pornography]; and perhaps I could never succeed in intelligibly doing so. But I know it when I see it, and the motion picture involved in this case is not that. [U.S. Supreme Court Justice Potter Stewart, concurring opinion, "Jacobellis v. Ohio," 1964]
In ancient contexts, often paired with rhypography, "genre painting of low, sordid, or unsuitable subjects." Pornocracy (1860) is "the dominating influence of harlots," used specifically of the government of Rome during the first half of the 10th century by Theodora and her daughters. Pornotopia (1966) was coined to describe the ideal erotic-world of pornographic movies.
porosity (n.): late 14c., from Old French porosité, from Medieval Latin porositas, from porus (see pore (n.)).
porous (adj.): late 14c., "full of pores," from Old French poros (14c., Modern French poreux), from Medieval Latin porosus; or directly from Latin porus "an opening" (see pore (n.)). Figurative use from 1640s.
porphyria (n.): metabolic disorder, 1923, from porphyrin (1910), the name of the type of chemical which, in imbalance, causes it, from German porphyrin, chemical name, from Greek porphyros "purple" (see purple) + -in (2). Some of the compounds are purple.
porphyrite (n.): 1796 as a modern mineral name, from porphyry + -ite (2). Related: Porphyritic.
porphyry (n.): type of ornamental stone, late 14c., porfurie, from Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites, a purple semi-precious stone quarried near the Red Sea in Egypt, from Greek porphyrites (lithos) "the purple (stone)," from porphyra (n.) "purple, purple dye" (see purple). Spelling Latinized mid-15c. Now used generally for a type of igneous rock without regard to color. Porphyrios was an ancient proper name.
porpoise (n.): early 14c., porpas, from Old French porpais (12c.) "porpoise," literally "pork fish," from porc "pork" (see pork (n.)) + peis "fish," from Latin piscis "fish" (see fish (n.)).

The Old French word probably is a loan-translation of a Germanic word meaning literally "sea-hog, mere-swine," such as Old Norse mar-svin, Old High German meri-swin, Middle Dutch mereswijn "porpoise" (the last of which also was borrowed directly into French and became Modern French marsouin).

Classical Latin had a similar name, porculus marinus (in Pliny), and the notion behind the name likely is a fancied resemblance of the snout to that of a pig.
porridge (n.): 1530s, porage "soup of meat and vegetables," alteration of pottage, perhaps from influence of Middle English porray, porreie "leek broth," from Old French poree "leek soup," from Vulgar Latin *porrata, from Latin porrum "leek." Spelling with -idge attested from c. 1600. Association with oatmeal is 1640s, first in Scottish.
porringer (n.): late 15c., alteration of potynger, potager "small dish for stew," from Middle English potage (see pottage) by the same course of changes that produced porridge; and with intrusive -n- by 1530s (compare passenger).
port (n.1): "harbor," Old English port "harbor, haven," reinforced by Old French port "harbor, port; mountain pass;" Old English and Old French words both from Latin portus "port, harbor," originally "entrance, passage," figuratively "place of refuge, asylum," from PIE *prtu- "a going, a passage," from root *per- (2) "to lead, pass over" (source also of Sanskrit parayati "carries over;" Greek poros "journey, passage, way," peirein "to pierce, run through;" Latin porta "gate, door," portare "passage," peritus "experienced;" Avestan peretush "passage, ford, bridge;" Armenian hordan "go forward;" Welsh rhyd "ford;" Old Church Slavonic pariti "to fly;" Old English faran "to go, journey," Old Norse fjörðr "inlet, estuary").

Meaning "left side of a ship" (looking forward from the stern) is attested from 1540s, from notion of "the side facing the harbor" (when a ship is docked). It replaced larboard in common usage to avoid confusion with starboard; officially so by Admiralty order of 1844 and U.S. Navy Department notice of 1846. Figurative sense "place of refuge" is attested from early 15c.; phrase any port in a storm first recorded 1749. A port of call (1810) is one paid a scheduled visit by a ship.
port (n.2): "gateway," Old English port "portal, door, gate, entrance," from Old French porte "gate, entrance," from Latin porta "city gate, gate; door, entrance," from PIE root *per- (2) "to lead, pass over" (see port (n.1)). Specific meaning "porthole, opening in the side of a ship" is attested from c. 1300.
port (n.3): "bearing, mien," c. 1300, from Old French port, from porter "to carry," from Latin portare (see port (n.1)).
port (n.4): type of sweet dark-red wine, 1690s, shortened from Oporto, city in northwest Portugal from which the wine originally was shipped to England; from O Porto "the port" (see port (n.1)).
port (v.): "to carry," from Middle French porter, from Latin portare "to carry" (see port (n.1)). Related: Ported; porting.
port-wine (n.): 1700, from port (n.4) + wine (n.).
portable (adj.): early 15c., from French portable "that can be carried," from Late Latin portabilis "that can be carried," from Latin portare "to carry" (see port (n.1)). Related: Portability.
portage (n.): early 15c., "action of carrying," said to be from Old French portage, Medieval Latin portaticum, though the meaning of these was "tax paid on entering a town," from Latin portare "to carry" (see port (n.1)). Sense of "carrying of boats from one navigable water to another" is from 1690s, reinforced in Canadian French.
portal (n.): late 14c., "gate, gateway," from Old French portal "gate" (Modern French portail) and directly from Medieval Latin portale "city gate, porch," from neuter of portalis (adj.) "of a gate," from Latin porta "gate" (see port (n.1)).
portcullis (n.): also port-cullis, c. 1300, from Old French porte coleice "sliding gate" (c. 1200, Modern French porte à coulisse), from porte "gate" (from Latin porta, from PIE root *per- (2); see port (n.1)) + coleice "sliding, flowing," fem. of coleis, from Latin colatus, past participle of colare "to filter, strain" (see colander).
Porte (n.): "Ottoman court at Constantinople," c. 1600, from French, in full, la Sublime Porte, literally "the high gate," translation of Arabic al-Bab al-'Ali, "lofty gate," official name of the central office of the Ottoman government (compare Vatican for "the Papacy," White House for "the United States"). Compare also mikado. Supposedly a reference to the ancient custom of holding royal audience in the doorway of a king's palace or tent.
porte-cochere (n.): gateway for carriages, 1690s, from French porte-cochère, from porte "gate" (from PIE root *per- (2) "to lead, pass over;" see port (n.1)) + cochère, fem. adjective from coche "coach" (see coach (n.)).
portend (v.): early 15c., from Latin portendere "foretell, reveal; point out, indicate," originally "to stretch forward," from por- (variant of pro-; see pro-) "forth, forward" + tendere "to stretch, extend" (see tenet). Related: Portended; portending.
portent (n.): 1560s, from Middle French portente, from Latin portentum "a sign, token, omen; monster, monstrosity," noun use of neuter of portentus, past participle of portendre (see portend).