A- (3) prefix meaning "not," from Gk a-, an- "not," from pie base *ne "not" (see un-)

perfusion --- 1574, from M.Fr. perfusion, from L. perfusionem (nom. perfusio) "a pouring over," from perfusus, pp. of perfundere "pour out," from per- "throughout" + fundere "pour" (see found (2)).

perhaps --- 1528, formed from M.E. per, par "by, through" + plural of hap "chance" (see happen), on model of peradventure, perchance, etc. which now have been superseded by this word.

peri --- 1777, from Pers. pari, from Avestan pairika. Race of superhuman female beings originally represented as malevolent, later as angelic genii (cf. sense evolution of Eng. fairy, to which it is not related).

peri- --- prefix meaning "around, about, enclosing," from Gk. peri (prep.) "around, about, beyond," cognate with Skt. pari "around, about, through," L. per (see per).

perianth --- envelope of a flower, 1706, from Fr. périanthe, from Mod.L. perianthium (17c.), lit. "that which is round the flower," from peri- + Gk. anthos "flower" (see anther).

pericardium --- 1576, Latinized form of Gk. perikardion "membrane around the heart" (Galen), from peri (prep.) "around, about" + kardia "heart" (see heart).

Pericles --- Athenian statesman (c.495-429 B.C.E.), from Gk. Perikles, lit. "far-famed," from peri "all around" + -kles "fame" (see Damocles). His leadership of Athens marks its intellectual and material zenith.

perigee --- point at which a celestial body is nearest the Earth, 1594, from Mod.L. perigeum (15c.), from Late Gk. peregeion, used by Ptolemy as a noun, properly neut. of adj. perigeios "near the earth," from peri ges, from peri "near" + ges, gen. of ge "earth."

perihelion --- point at which a celestial body is nearest the Sun, 1690, coined in Mod.L. (perihelium) by Kepler (1596) from Gk. peri "near" + helios "sun" (see sol), and subsequently re-Grecianized.

peril --- c.1225, from O.Fr. peril (10c.), from L. periculum "an attempt, risk, danger," with instrumentive suffix -culum and root of ex-peri-ri "to try," cognate with Gk. peria "trial, attempt, experience," empeiros "experienced," O.Ir. aire "vigilance," Goth. ferja "watcher," O.E. fær "danger, fear," all ult. from PIE base *per- "to lead across."

perilous --- c.1290, from O.Fr. perillous (Fr. périlleux) "dangerous, hazardous," from L. periculosus, from periculum "dangerous" (see peril).

perimeter --- 1592, "line around a figure or surface," from L. perimetros, from Gk. perimetros "circumference," from peri- "around" + metron "measure" (see meter (2)). Military sense of "boundary of a defended position" is attested from 1943.

perineum --- region of the body between the anus and the genital organs, 1632, from M.L. perinaeon, L.L. perineum (c.440), from Gk. perinaion, perinaios, from peri- "near" + inan "to carry off by evacuation," of unknown origin.

period --- 1413, "course or extent of time," from M.L. periodus "recurring portion, cycle," from L. periodus "a complete sentence," also "cycle of the Greek games," from Gk. periodos "rounded sentence, cycle, circuit, period of time," lit. "going around," from peri- "around" + hodos "a going, way, journey" (see cede). Sense of "repeated cycle of events" led to that of "interval of time." Meaning "dot marking end of a sentence" first recorded 1609, from similar use in M.L. Sense of "menstruation" dates from 1822. Educational sense of "portion of time set apart for a lesson" is from 1876. Sporting sense attested from 1898.

periodic --- 1642, from Fr. périodique (14c.), from L. periodicus, from periodus (see period). Periodical "magazine that publishes regularly" is first attested 1798. Periodic table in chemistry is from notion of the arrangement, in which similar properties recur at intervals in elements in the same area as you read down the rows of the table. This sense of the word is attested fromj 1872.

periodontal --- 1854, lit. "around the tooth," from peri- (q.v.) + Gk. odon (gen. odontos) "tooth."

peripatetic --- c.1400, n., "disciple of Aristotle," from O.Fr. perypatetique (14c.), from L. peripateticus "pertaining to the disciples or philosophy of Aristotle," from Gk. peripatetikos "given to walking about" (especially while teaching), from peripatein, from peri- "around" + patein "to walk." Aristotle's custom was to teach while strolling through the Lyceum in Athens. In Eng., the philosophical meaning is older than that of "person who wanders about" (1617). As an adj., attested in Eng. 1566 in the philosophical sense, 1642 in the lit. sense.

periphery --- 1390, from O.Fr. periferie, from L.L. peripheria, from Gk. peripheria "circumference, outer surface," lit. "a carrying around," from peripheres "rounded, moving round, revolving," peripherein "carry or move round," from peri- "round about" + pherein "to carry" (see infer). Peripheral first recorded 1808.

periphrasis --- 1533, from L. periphrasis "circumlocution," from Gk. periphrasis, from periphrazein "speak in a roundabout way," from peri- "round about" + phrazein "to express."

periscope --- 1899, formed in Eng. from peri- "around" + -scope "instrument for viewing." Earlier (1865) a technical term in photography.

perish --- c.1250, from periss- prp. stem of O.Fr. perir, from L. perire "to be lost, perish," lit. "to go through," from per- "through, completely, to destruction" + ire "to go." Perishables in ref. to foodstuffs is attested from 1895.

peristaltic --- 1655, from Mod.L., from Gk. peristalikos (Galen), lit. "contracting around," from peri- (q.v.) + stalsis "checking, constriction," related to stellein "to put in order, draw together."

peritoneum --- 1541, from L.L. peritonaeum (c.420), from Gk. peritonaion "abdominal membrane," lit. "part stretched over," from neut. of peritonaios "stretched over," from peri- "around" + teinein "to stretch" (see tenet).

periwig --- 1529, perwyke, popular corruption of perruck, from M.Fr. perruque (see peruke).

periwinkle (1) --- evergreen plant, 1501, dim. of parvink (12c.), from O.E. perwince, from L.L. pervinca "periwinkle" (4c.), from L., from pervincire "to entwine, bind," from per- "thoroughly" + vincire "to bind, fetter."

periwinkle (2) --- kind of sea snail, 1530, alt. of O.E. pinewincle, probably by infl. of M.E. parvink (see periwinkle (1)), from O.E. pine- (probably from L. pina "mussel," from Gk. pine) + wincel "corner."

perjury --- 1387, "act of swearing to a statement known to be false," via Anglo-Fr. parjurie (1292) and O.Fr. parjurie, both from L. perjurium "false oath," from perjurare "swear falsely," from per- "away, entirely" + jurare "to swear" (see jury (n.)). The verb perjure is attested from 1453 (implied in perjured).

perk (n.) --- 1869, shortened and altered form of perquisite (q.v.); 1934 as shortened and altered form of percolate (see percolation).

perk (v.) --- c.1380, "to make oneself trim or smart," perhaps from O.N.Fr. perquer "to perch" (Fr. percher; see perch (1)), on notion of a bird preening its plumage. Sense of "raise oneself briskly" is first attested 1529; perk up "recover liveliness" is from 1656; the adj. perky was formed 1855 (first found in Tennyson).

perm (n.) --- 1927, shortened form of permanent wave (1909). The verb is first recorded 1928.

permafrost --- 1943, coined in Eng. by S.W. Muller from perm(anent) frost.

permanent --- 1432, from M.Fr. permanent (14c.), from L. permanentem (nom. permanens) "remaining," prp. of permanere "endure, continue, stay to the end," from per- "through" + manere "stay" (see mansion).

permeable --- 1432, from L. permeabilis "that can be passed through, passable," from L. permeare "to pass through," from per- "through" + meare "to pass," from PIE base *mei-/*moi- "to change" (see mutable). The verb permeate first is attested 1660.

Permian --- 1841, "pertaining to the uppermost strata of the Paleozoic era," named by British geologist Sir Roderick Impey Murchison (1792-1871) for the region of Perm in northwestern Russia, where rocks from this epoch are found.

permission --- c.1410, from L. permissionem (nom. permissio), from permissus, pp. of permittere (see permit).

permissive --- 1603, "allowing to pass through," from O.Fr. permissif, from L. permissus (see permission). In sense of "tolerant, liberal" it is first recorded 1956; by 1966 it had definite overtones of sexual freedom.

permit (v.) --- 1489, from M.Fr. permetre, from L. permittere "give up, allow, allow to pass through," from per- "through" + mittere "let go, send." The noun is first recorded 1714.

permutation --- 1362, from O.Fr. permutacion (14c.), from L. permutationem (nom. permutatio), from permutatus, pp. of permutare "change thoroughly, exchange," from per- "thoroughly" + mutare "to change" (see mutable).

pernicious --- 1521, from M.Fr. pernicios (13c., Fr. pernicieux), from L. perniciosus "destructive," from pernicies "destruction, death, ruin," from per- "completely" + necis "violent death, murder," related to necare "to kill," nocere "to hurt, injure, harm," noxa "harm, injury" (see noxious).

pernickety --- 1808, "precise, fastidious," extended form of Scot. pernicky, of uncertain origin, perhaps somehow from particular.

peroration --- c.1440, from L. perorationem (nom. peroratio) "the ending of a speech or argument of a case," from peroratus, pp. of perorare "argue a case to the end, bring a speech to a close," from per- "to the end" + orare "to speak, plead" (see orator).

peroxide --- 1804, formed in Eng. from per- "large amount" + oxide (q.v.). Peroxide blonde is attested from 1918.

perpendicular (adj.) --- c.1391, from O.Fr. perpendiculer, from L. perpendicularis "vertical, as a plumb line," from perpendiculum "plumb line," from perpendere "balance carefully," from per- "thoroughly" + pendere "to weigh, to hang" (see pendant).

perpetrate --- c.1450 (implied in perpetration), from L. perpetratus, pp. of perpetrare "to perform, to accomplish," from per- "completely" + patrare "carry out," originally "bring into existence," from pater "father" (see father). Neither good nor bad in L., first used in Eng. in statutes, hence its sense of "to perform criminally." Perpetrator is 1570, from L.L. perpetrator, from L. perpetrare. Police slang shortening perp (e.g. perp walk) is Amer.Eng., by 1940s.

perpetual --- c.1340, from O.Fr. perpetuel (12c.), from L. perpetualis "universal," in M.L. "permanent," from perpetuus "continuous, universal," from perpetis, gen. of Old L. perpes "lasting," probably from per- "through" + root of petere "to seek, go to, aim at" (see petition). The verb perpetuate is first recorded 1530; perpetuity is from 1406. Perpetual motion is attested from 1593.

perplexity --- c.1300, from L.L. perplexitas, from L. perplexus "confused, involved," from per- "completely" + plexus "entangled," pp. of plectere "to twine." Perplex (v.) is attested from 1477, but originally and until 17c. only in pp. form perplexed.

perquisite --- 1450, "property acquired other than by inheritance," from M.L. perquisitum "thing gained, profit," in L., "thing sought after," from neut. pp. of perquirere "to seek, ask for," from per- "thoroughly" + quærere "to seek" (see query). General meaning "fee or profit on top of regular wages" first recorded 1565.

Perrier --- proprietary name of a natural mineral water from southern France, first attested 1907.

persecution --- c.1340, "oppression for the holding of a belief or opinion," from O.Fr. persecution (12c.), from L. persecutionem (nom. persecutio), noun of action from persequi "pursue, start a legal action," from per- "through" + sequi "follow" (see sequel). The verb persecute is attested from 1482 in the sense of "to oppress for the holding of a belief or opinion," from M.Fr. persécuter "pursue, torment, open legal action" (14c.), from L. persecutus, pp. of persequi. Psychological persecution complex is recorded from 1961; earlier persecution mania (1892).

Persephone --- wife of Hades, queen of the netherworld, identified with Kore, daughter of Zeus and Demeter, from Gk. Persephone (see person).

Perseus --- son of Zeus and Danaë, slayer of Medusa, from Gk. Perseus, of unknown origin.

persevere --- c.1340 (implied in perseverance), from O.Fr. perseverer, from L. perseverare "continue steadfastly, persist," from persevereus "very strict, earnest," from per- "very" + severus "strict" (see severity).

Persian --- c.1400, percynne (adj.), O.E. Perse (n.), both from L. *Persianus (the adj. via O.Fr. persien), from Persia "Persia," from Gk. Persis, from O.Pers. Parsa (cf. Pers. Fars, Heb. Paras, Arab. Faris). First record of Persian cat is 1821, in Lord Byron.

persiflage --- 1757, from Fr. persiflage, from persifler "to banter," from L. per- "through" + Fr. siffler "to whistle, hiss," from collateral form of L. sibilare "to hiss," possibly of imitative origin.

persimmon --- 1612, from Powhatan (Algonquian) pasimenan "fruit dried artificially," from pasimeneu "he dries fruit," containing proto-Algonquian */-min-/ "fruit, berry."

Persis --- fem. proper name, from L., from Gk. Persis, lit. "a Persian woman," related to Perses "Persian" (see Persian).

persist --- 1538, from M.Fr. persister (14c.), from L. persistere "continue steadfastly," from per- "thoroughly" + sistere "come to stand, cause to stand still" (see assist). Persistence is attested from 1546; persistent is from 1826.

persnickety --- 1905, alteration of pernickety (q.v.).

person --- c.1225, from O.Fr. persone "human being" (12c., Fr. personne), from L. persona "human being," originally "character in a drama, mask," possibly borrowed from Etruscan phersu "mask." This may be related to Gk. Persephone. The use of -person to replace -man in compounds and avoid alleged sexist connotations is first recorded 1971 (in chairperson). Personify first recorded 1727. Personable "pleasing in one's person" is first attested c.1430. In person "by bodily presence" is from 1568. Person-to-person first recorded 1919, originally of telephone calls.

persona --- 1917, "outward or social personality," a Jungian psychology term, from L. persona "person" (see person). Used earlier (1909) by Ezra Pound in the sense "literary character representing voice of the author." Persona grata (1882) is from L.L., lit. "an acceptable person," originally applied to diplomatic representatives acceptable to the governments to which they were sent; persona non grata is attested from 1904 (pl. is personæ non gratæ).

personage --- 1461, "body of a person" (with regard to appearance), from O.Fr. personage (13c.), from M.L. personaticum (1057), from persona (see person). Meaning "a person of high rank or distinction" is attested from 1503; as a longer way to say person, the word was in use from c.1555 (but often slyly ironical, with suggestion that the subject is overly self-important).

personal (adj.) --- 1387, "pertaining to the self," from O.Fr. personel (12c., Fr. personnel), from L. personalis "pertaining to a person," from persona (see person). Meaning "aimed at some particular person" (usually in a hostile manner) first attested 1614. The noun sense of "newspaper item about private matters" is attested from 1888. As "a classified ad addressed to an individual," it is recorded from 1861. Personal computer is from 1976.

personality --- c.1380, "quality or fact of being a person," from M.L. personalitatem (nom. personalitas), from L. personalis (see personal). Sense of "a distinctive character" is first recorded 1795, from Fr. personnalité.

personify --- 1727 "to attribute personal form to things or abstractions" (especially as an artistic or literary technique), from Fr. personnifier (17c.), as if from L. *personificare, from persona (see person) + -ficare "to make." Personification in the sense of "embodiment of a quality in a person" is attested from 1807.

personnel --- 1837, from Fr. personnel (a contrastive term to materiél), noun use of personnel (adj.) "personal," from O.Fr. personel (see personal).

perspective --- c.1380, "science of optics," from O.Fr. perspective, from M.L. perspectiva ars "science of optics," from fem. of perspectivus "of sight, optical" from L. perspectus, pp. of perspicere "inspect, look through," from per- "through" + specere "look at" (see scope (1)). Sense of "art of drawing objects so as to give appearance of distance or depth" is first found 1598, influenced by It. prospettiva, an artists' term. The fig. meaning "mental outlook over time" is first recorded 1762.

perspicacity --- 1548, from M.Fr. perspicacité (15c.), from L.L. perspicacitas "sharp-sightedness, discernment," from L. perspicax "sharp-sighted," from perspicere "look through" (see perspective).

perspiration --- 1611, from Fr. perspiration (1561), noun of action from perspirer "perspire," from L. perspirare "blow or breathe constantly," from per- "through" + spirare "to breathe, blow" (see spirit). Applied to excretion of invisible moistures through the skin (1626), hence used as a euphemism for "sweat" from 1725.

persuasion --- 1382, "action of inducing (someone) to believe (something)," from O.Fr. persuasion (14c.), from L. persuasionem (nom. persuasio) "a convincing, persuading," from persuadere "persuade," from per- "thoroughly, strongly" + suadere "to urge, persuade," from PIE *swad-. Meaning "religious belief, creed" is from 1623. The verb persuade is first recorded 1513.

pert --- c.1300 (implied in pertly), "evident, unconcealed," aphetic form of apert "open, frank," from O.Fr. apert, from L. apertus, pp. of aperire "to open" (see overt). Sense of "saucy, bold" first recorded c.1386. Less pejorative meaning "lively, brisk, in good spirits" (c.1500) survives in U.S. dial. peart (with M.E. alternate spelling).

pertain --- c.1350, from O.Fr. partenir "to belong," from L. pertinere "to reach, stretch, relate, have reference to," from per- "through" + tenere "to hold" (see tenet).

pertinacity --- 1504, from M.Fr. pertinacité (1419), from O.Fr. pertinace "obstinate," from L. pertinacem (nom. pertinax) "very firm, tenacious," from per- "very" + tenax (see tenacious).

pertinent --- c.1380, from Anglo-Fr. purtinaunt (1278), from O.Fr. partenant (1246), from L. pertinentem (nom. pertinens) "pertaining," prp. of pertinere "to relate, concern" (see pertain).

perturb --- c.1374 (implied in perturbation), probably via O.Fr. perturber (14c.), from L. perturbare "to confuse, disorder, disturb," from per- "through" + turbare "disturb, confuse," from turba "turmoil, crowd" (see turbid).

Peru --- from Sp. Peru, said to be from Quechua pelu "river."

peruke --- 1547, "natural head of hair," from M.Fr. perruque (late 15c.), from It. perrucca "head of hair, wig," of uncertain origin; supposed to be connected to L. pilus "hair" (It. pelo, O.Fr. pel), "but the phonetic difficulties are considerable" [O.E.D.]. Meaning "artificial head of hair, periwig" is attested from 1565.

peruse --- 1479, "use up, wear out, go through," from M.E. per- "completely" + use (q.v.). Meaning "read carefully" is first recorded 1532, but this may be a separate formation.

pervade --- 1653, from L. pervadere "spread or go through," from per- "through" + vadere "to go" (see vamoose). Pervasive is attested from c.1750.

perverse --- c.1369, "wicked," from O.Fr. pervers, from L. perversus "turned away (from what is right), contrary, askew," pp. of pervertere "to corrupt" (see pervert). The L. word is glossed in O.E. by forcerred, from p.p. of forcyrran "to avoid," from cierran "to turn, return." Meaning "wrong, not in accord with what is accepted" is from c.1568; sense of "obstinate, stubborn" is from 1579. It keeps the non-sexual senses of pervert (v.) and allows the psychological ones to go with perverted.

perversion --- 1388, "action of turning aside from truth, corruption, distortion" (originally of religious beliefs), from pervert (v.) (q.v.). Psychological sense of "disorder of sexual behavior in which satisfaction is sought through channels other than those of normal heterosexual intercourse" is from 1892, originally including homosexuality.

pervert (v.) --- c.1300 (trans.), "to turn someone aside from a right religious belief to a false or erroneous one," from O.Fr. pervertir, from L. pervertere "corrupt, turn the wrong way, turn about," from per- "away" + vertere "to turn" (see versus). The noun is 1661, from the verb. Replaced native froward, which embodies the same image. The noun is attested from 1661, "one who has forsaken a doctrine or system regarded as true, apostate;" psychological sense of "one who has a perversion of the sexual instinct" is attested from 1897 (Havelock Ellis), originally esp. of homosexuals. Perv, short for sexual pervert (n.), is first recorded 1944.

pesky --- 1775, originally in New England dialect, perhaps a dial. formation from pest (cf. plaguy "confounded, annoying, disagreeable"). Partridge suggests an origin in Essex dialect.

peso --- Spanish coin, 1555, from Sp., lit. "a weight," from L. pensum, properly pp. of pendere "to hang, to cause to hang" (see pendant). Formerly either of silver (peso de plata) or gold (peso de oro).

pessary --- c.1400, from L.L. pessarium, from Gk. pessarion "medicated tampon of wool or lint," dim. of pessos "pessary," earlier "oval stone used in games," perhaps of Semitic origin.

pessimism --- 1794 "worst condition possible," borrowed (by Coleridge) from Fr. pessimisme, formed (on model of Fr. optimisme) from L. pessimus "worst," originally "bottom-most," from PIE *ped-samo-, superl. of base *pes- "foot" (see foot). As a name given to the doctrines of Schopenhauer, Hartmann, etc., that this is the worst possible world, or that everything tends toward evil, it is first recorded 1878, from Ger. pessimismus (Schopenhauer, 1819). Pessimist "one who habitually expects the worst" is first recorded 1836, from Fr. pessimiste; pessimistic formed in Eng. 1868.

pest --- 1553 (in imprecations, "a pest upon ____," etc.), "plague, pestilence," from M.Fr. peste (1539), from L. pestis "deadly contagious disease." Meaning "noxious or troublesome person or thing" first recorded 1609.

pester --- 1524, "to clog, entangle, encumber," probably aphetic of M.Fr. empestrer "place in an embarrassing situation" (Fr. empêtrer, Walloon epasturer), from V.L. *impastoriare "to hobble" (an animal), from L. im- "in" + M.L. pastoria (chorda) "rope to hobble an animal," noun use of L. pastoria, fem. of pastorius "of a herdsman," from pastor "herdsman," from pascere "to graze." Sense of "annoy, trouble" (1562) is from influence of pest (q.v.).

pesticide --- 1939, a hybrid coined from Eng. pest (q.v.) + -cide, from L. cidium "a killing," from caedere "to cut down, kill" (see concise).

pestiferous --- 1458, mischievous, pernicious, fig. use of L. pestiferus "that brings plague or destruction," variant of pestifer "bringing plague," from pestis "plague" + ferre "carry" (see infer).

pestilence --- 1303, from O.Fr. pestilence, from L. pestilentia "plague," noun of action from pestilentem (nom. pestilens) "infected, unwholesome, noxious," from pestis "deadly disease, plague."

pestle --- 1272, from O.Fr. pestel, from L. pistillum "pounder, pestle," related to pinsere "to pound," from PIE *pis-to-, suffixed form of base *peis- "to crush" (cf. Skt. pinasti "pounds, crushes," pistah "anything ground, meal," Gk. ptissein "to winnow," O.C.S. piso, pichati "to push, thrust, strike," pisenica "wheat," Rus. pseno "millet").

pesto --- olive oil-based pasta sauce, 1937, from It. pesto, contracted form of pestato, pp. of pestare "to pound, to crush," in ref. to the crushed herbs and garlic in it, from L. root of pestle.

pet (1) --- tamed animal, originally Scot. and northern England dial., of unknown origin. Sense of "indulged child" (1508) is recorded slightly earlier than that of "animal kept as a favorite" (1539), but the latter may be the primary meaning. Probably associated with or influenced by petty. The verb is 1629 meaning "treat as a pet;" the sense of "to stroke" is first found 1818. Slang sense of "kiss and caress" is from 1920 (implied in petting, in F. Scott Fitzgerald). Teacher's pet is attested from 1914.