porphyria (n.) Look up porphyria at Dictionary.com
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.) Look up porphyrite at Dictionary.com
1796 as a modern mineral name, from porphyry + -ite (2). Related: Porphyritic.
porphyry (n.) Look up porphyry at Dictionary.com
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.) Look up porpoise at Dictionary.com
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.) Look up porridge at Dictionary.com
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.) Look up porringer at Dictionary.com
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) Look up port at Dictionary.com
"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" (cognates: 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) Look up port at Dictionary.com
"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- (see port (n.1)). Specific meaning "porthole, opening in the side of a ship" is attested from c. 1300.
port (n.3) Look up port at Dictionary.com
"bearing, mien," c. 1300, from Old French port, from porter "to carry," from Latin portare (see port (n.1)).
port (n.4) Look up port at Dictionary.com
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.) Look up port at Dictionary.com
"to carry," from Middle French porter, from Latin portare "to carry" (see port (n.1)). Related: Ported; porting.
port-wine (n.) Look up port-wine at Dictionary.com
1700, from port (n.4) + wine (n.).
portable (adj.) Look up portable at Dictionary.com
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.) Look up portage at Dictionary.com
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.) Look up portal at Dictionary.com
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.) Look up portcullis at Dictionary.com
also port-cullis, c. 1300, from Old French porte coleice "sliding gate" (c. 1200, Modern French porte à coulisse), from porte "gate" (see port (n.2)) + coleice "sliding, flowing," fem. of coleis, from Latin colatus, past participle of colare "to filter, strain" (see colander).
Porte (n.) Look up Porte at Dictionary.com
"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.) Look up porte-cochere at Dictionary.com
gateway for carriages, 1690s, from French porte-cochère, from porte "gate" (see port (n.2)) + cochère, fem. adjective from coche "coach" (see coach (n.)).
portend (v.) Look up portend at Dictionary.com
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.) Look up portent at Dictionary.com
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).
portentous (adj.) Look up portentous at Dictionary.com
1540s, from Latin portentosus "monstrous, marvelous, threatening," from portentem "portent" (see portend). Related: Portentously.
porter (n.1) Look up porter at Dictionary.com
"person who carries," late 14c. (mid-13c. as a surname), from Anglo-French portour, Old French porteor "porter, bearer; reporter" (12c.), from Late Latin portatorem (nominative portator) "carrier, one who carries," from past participle stem of Latin portare "to carry" (see port (n.1)).
porter (n.2) Look up porter at Dictionary.com
"doorkeeper, janitor," mid-13c. (late 12c. as a surname), from Anglo-French portour, Old French portier "gatekeeper" (12c.), from Late Latin portarius "gatekeeper," from Latin porta "gate" (see port (n.2)).
porter (n.3) Look up porter at Dictionary.com
type of dark beer, 1734, short for porter's ale (1721), from porter (n.1), because the beer was made for or preferred by porters and other laborers, being cheap and strong.
porterhouse (n.) Look up porterhouse at Dictionary.com
also porter-house, "restaurant or chophouse where porter is served," 1754, from porter (n.3) + house (n.). Porterhouse steak (1841) is said to be from a particular establishment in New York City.
portfolio (n.) Look up portfolio at Dictionary.com
1722, porto folio; 1719 as port folio, from Italian portafoglio "a case for carrying loose papers," from porta, imperative of portare "to carry" (see port (n.1)) + foglio "sheet, leaf," from Latin folium (see folio). Meaning "official documents of a state department" is from 1835. A minister without portfolio is one not in charge of a particular department. Meaning "collection of securities held" is from 1930; portfolio investment is from 1955.
porthole (n.) Look up porthole at Dictionary.com
also port-hole, 1590s, from port (n.2) + hole (n.).
portico (n.) Look up portico at Dictionary.com
c. 1600, from Italian portico, from Latin porticus "colonnade, arcade, covered walk, porch," from porta "gate" (see port (n.1)). Especially of the Painted Porch in Athens.
portiere (n.) Look up portiere at Dictionary.com
door curtain, 1843, from French portière, from Medieval Latin portaria, fem. singular of Latin portarius "belonging to a door or gate" (see porter (n.2)).
portion (n.) Look up portion at Dictionary.com
early 14c., "allotted part, share," from Old French porcion "part, portion" (12c., Modern French portion) and directly from Latin portionem (nominative portio) "share, part," accusative of the noun in the phrase pro portione "according to the relation (of parts to each other)" (see proportion). From late 14c. in general sense of "section into which something is divided."
portion (v.) Look up portion at Dictionary.com
"to divide in portions," early 14c., from Old French porcioner "share out, divide in portions," from porcion (see portion (n.)). Related: Portioned; portioning.
Portland Look up Portland at Dictionary.com
in Portland cement, 1720, named by its inventor, English mason Joseph Aspdin, from resemblance of the color to the stone of Portland peninsula on the coast of Dorsetshire. The place name is literally "land surrounding a harbor," Old English Portlanda. Portland, Maine, U.S.A., took its name 1786, for the place in England. Portland, Oregon, was said to have been named for the city in Maine, which won the honor by a coin toss over Boston.
portly (adj.) Look up portly at Dictionary.com
early 15c., "stately, dignified," from port (n.3) "bearing, carriage" + -ly (1). Meaning "stout" is first recorded 1590s.
portmanteau (n.) Look up portmanteau at Dictionary.com
1580s, "traveling case or bag for clothes and other necessaries," from Middle French portemanteau "traveling bag," originally "court official who carried a prince's mantle" (1540s), from porte, imperative of porter "to carry" (see porter (n.1)) + manteau "cloak" (see mantle (n.)).

Portmanteau word "word blending the sound of two different words" (1882), coined by "Lewis Carroll" (Charles L. Dodgson, 1832-1898) for the sort of words he invented for "Jabberwocky," on notion of "two meanings packed up into one word." As a noun in this sense from 1872.
portobello Look up portobello at Dictionary.com
type of mushroom, by 1986, no agreed-upon theory accounts for the name, which seems to be a marketing coinage. London's Portobello Road (one suggested source of the mushroom name) originally was the lane to Porto Bello House, named for the Panamanian place captured by the British under Vernon in 1739.
portrait (n.) Look up portrait at Dictionary.com
1560s, "a figure, drawn or painted," a back formation from portraiture or directly from Middle French portrait, from Old French portret (13c.), noun use of past participle of portraire "to paint, depict" (see portray). Especially of the head and face of a person.
portraiture (n.) Look up portraiture at Dictionary.com
mid-14c., from Old French portraiture "portrait, image, portrayal, resemblance" (12c.), from portrait (see portrait).
portray (v.) Look up portray at Dictionary.com
mid-13c., "to draw, paint" (something), from Anglo-French purtraire, Old French portraire "to draw, to paint, portray" (12c.), literally "trace, draw forth," from por- "forth" (from Latin pro-; see pro-) + traire "trace, draw," from Latin trahere "to drag, draw" (see tract (n.1)). Meaning "depict in words, describe" is from late 14c. Related: Portrayed; portraying.
portrayal (n.) Look up portrayal at Dictionary.com
1834, from portray + -al (2). The idea formerly was expressed by portray (n.), 1610s.
portsider (n.) Look up portsider at Dictionary.com
"left-handed person," 1913, American English baseball slang, from port (n.1) in the nautical sense + side (n.).
Portugal Look up Portugal at Dictionary.com
late 14c., Portyngale, from Medieval Latin Portus Cale (Roman name of modern Oporto), "the port of Gaya," from Latin portus "harbor, port" (see port (n.1)). Alfonso, Count of Portucale, became the first king of Portugal.
Portuguese (n.) Look up Portuguese at Dictionary.com
1610s, the language, or a resident, of Portugal; 1660s as an adjective, from Portuguese Portuguez (see Portugal + -ese). The ending was vulgarly mistaken for a plural in English, and false singular Portugee (1830) was formed (compare Chinee from Chinese). For Portuguese man-of-war, see man-of-war.
posable (adj.) Look up posable at Dictionary.com
1972 of questions; 1975 of action figures; from pose (v.1 and 2) + -able.
posada (n.) Look up posada at Dictionary.com
"inn," 1763, from Spanish posada "home, lodging," from posar "to repose, rest, lodge," from Latin pausare "to cease, lay down" (see pause (n.)).
pose (v.1) Look up pose at Dictionary.com
late 14c., posen, "suggest (something is so), suppose, assume; grant, concede," from Old French poser "put, place, propose," a term in debating, from Late Latin pausare "to halt, rest, cease, pause" (source also of Italian posare, Spanish posar; see pause (v.)). The Late Latin verb also had a transitive sense, "cause to pause or rest," and hence the Old French verb (in common with cognates in Spanish, Italian, Portuguese) acquired the sense of Latin ponere (past participle positus) "to put, place," by confusion of the similar stems. Meaning "put in a certain position" in English is from early 15c. Sense of "assume a certain attitude" is from 1840; the transitive sense (as an artist's model, etc.) is from 1859. Related: Posed; posing.
One of the most remarkable facts in F[rench] etymology is the extraordinary substitution whereby the Low Lat. pausare came to mean 'to make to rest, to set,' and so usurped the place of the Lat. ponere, to place, set, with which it has no etymological connection. And this it did so effectually as to restrict the F. pondre, the true equivalent of Lat. ponere, to the sense of 'laying eggs;' whilst in all compounds it completely thrust it aside, so that compausare (i.e. F. composer) took the place of Lat. componere, and so on throughout. Hence the extraordinary result, that whilst the E. verbs compose, depose, impose, propose, &c. exactly represent in sense the Lat. componere, deponere, imponere, proponere, &c., we cannot derive the E. verbs from the Lat. ones since they have (as was said) no real etymological connection. [W.W. Skeat, "Etymological Dictionary of the English Language," 1898]
pose (v.2) Look up pose at Dictionary.com
"to puzzle, confuse, perplex," 1590s, earlier "question, interrogate" (1520s), probably from Middle French poser "suppose, assume," from Old French poser "to put, place, set" (see pose (v.1)). Also in some cases a shortening of English appose "examine closely," and oppose. Related: Posed; posing.
pose (n.) Look up pose at Dictionary.com
"act of posing the body," 1818, from pose (v.1), in a sense developed in the French cognate. Figuratively from 1884.
Poseidon (n.) Look up Poseidon at Dictionary.com
Greek god of the sea and earthquakes, Greek Poseidon (Doric Poteidan), of uncertain origin.
poser (n.) Look up poser at Dictionary.com
"one who practices an affected attitude," 1881, agent noun from pose (v.1); revived in teen-ager slang by 1983. Meaning "question that puzzles" is from 1793 from pose (v.2); earlier it meant "one who asks testing questions" (1580s).
poseur (n.) Look up poseur at Dictionary.com
"one who practices affected attitudes," 1866, from French poseur, from verb poser "affect an attitude or pose," from Old French poser "to put, place, set" (see pose (v.1)). The word is English poser in French garb, and thus could itself be considered an affectation.