periwig (n.) Look up periwig at Dictionary.com
1520s, perwyke, popular corruption of perruck, from Middle French perruque (see peruke).
periwinkle (n.1) Look up periwinkle at Dictionary.com
evergreen plant, c.1500, diminutive of parvink (12c.), from Old English perwince, from Late Latin pervinca "periwinkle" (4c.), from Latin, perhaps from pervincire "to entwine, bind," from per- "thoroughly" (see per) + vincire "to bind, fetter" (see wind (v.1)).
periwinkle (n.2) Look up periwinkle at Dictionary.com
kind of sea snail, 1520s, apparently an alteration of Old English pinewincle (probably by influence of Middle English parvink; see periwinkle (n.1)); from Old English pine-, which probably is from Latin pina "mussel," from Greek pine. The second element is wincel "corner; spiral shell," from Proto-Germanic *winkil-, from PIE root *weng- "to bend, curve" (see wink (v.)).
perjure (v.) Look up perjure at Dictionary.com
mid-15c. "swear falsely" (implied in perjured; late 13c. in Anglo-French), from Old French parjurer "to break one's word, renege on a promise" (11c.), from Latin periurare "to swear falsely, break one's oath" (see perjury). Reflexive sense is from 18c.
perjury (n.) Look up perjury at Dictionary.com
late 14c., "act of swearing to a statement known to be false," via Anglo-French perjurie (late 13c.) and Old French parjurée "perjury, false witness," both from Latin periurium "a false oath," from periurare "swear falsely," from per- "away, entirely" (see per) + iurare "to swear" (see jury (n.)). Related: Perjurious.
perk (v.) Look up perk at Dictionary.com
late 14c., "to make oneself trim or smart," perhaps from Old North French perquer "to perch" (Modern French percher; see perch (n.1)), on notion of a bird preening its plumage. Sense of "raise oneself briskly" is first attested 1520s; perk up "recover liveliness" is from 1650s. Related: Perked; perking.
perk (n.) Look up perk at Dictionary.com
1869, shortened and altered form of perquisite (q.v.); as a verb, 1934 as shortened and altered form of percolate.
perky (adj.) Look up perky at Dictionary.com
1820, from perk (v.) + -y (2). Of young women's breasts since at least 1937. Related: Perkily; perkiness.
perm (n.) Look up perm at Dictionary.com
1927, shortened form of permanent wave (1909). The verb is first recorded 1928.
permaculture (n.) Look up permaculture at Dictionary.com
by 1978, from permanent + agriculture or culture.
permafrost (n.) Look up permafrost at Dictionary.com
1943, coined in English by Russian-born U.S. geologist Siemon W. Muller (1900-1970) from perm(anent) frost.
permanence (n.) Look up permanence at Dictionary.com
early 15c., from Middle French permanence and directly from Medieval Latin permanentia (early 14c.), from Latin permanens (see permanent). Related: Permanency.
permanent (adj.) Look up permanent at Dictionary.com
early 15c., from Middle French permanent (14c.) or directly from Latin permanentem (nominative permanens) "remaining," present participle of permanere "endure, hold out, continue, stay to the end," from per- "through" (see per) + manere "stay" (see mansion). As a noun meaning "permanent wave," by 1909. Of clothing, permanent press attested from 1964.
permanently (adv.) Look up permanently at Dictionary.com
late 15c., from permanent + -ly (2).
permeability (n.) Look up permeability at Dictionary.com
1733, from permeable + -ity, or else from French perméabilité.
permeable (adj.) Look up permeable at Dictionary.com
early 15c., from Late Latin permeabilis "that can be passed through, passable," from Latin permeare "to pass through, go over," from per- "through" (see per) + meare "to pass," from PIE root *mei- (1) "to change" (see mutable). Related: Permeably.
permeant (adj.) Look up permeant at Dictionary.com
1640s, from Latin permeantem (nominative permeans), present participle of permeare "to pass through" (see permeable).
permeate (v.) Look up permeate at Dictionary.com
1650s, from Latin permeatus, past participle of permeare "to pass through" (see permeable). Related: Permeated; permeating.
permeation (n.) Look up permeation at Dictionary.com
1620s, noun of action from Latin permeare (see permeate).
Permian Look up Permian at Dictionary.com
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.
permissible (adj.) Look up permissible at Dictionary.com
early 15c., from Old French permissible (15c.) and directly from Medieval Latin permissibilis, from permiss-, past participle stem of Latin permittere (see permit (v.)).
permission (n.) Look up permission at Dictionary.com
early 15c., from Latin permissionem (nominative permissio), noun of action from past participle stem of permittere (see permit (v.)).
permissive (adj.) Look up permissive at Dictionary.com
c.1600, "allowing to pass through," from Old French permissif, from Latin permiss-, past participle stem of permittere "to let go, let pass, let loose" (see permit (v.)). In sense of "tolerant, liberal" it is first recorded 1956; by 1966 it had definite overtones of sexual freedom. Earlier it meant "permitted, allowed" (early 15c.). Related: Permissively; permissiveness.
permit (v.) Look up permit at Dictionary.com
late 15c., from Middle French permetre and directly from Latin permittere "let pass, let go, let loose; give up, hand over; let, allow, grant, permit," from per- "through" (see per) + mittere "let go, send" (see mission). Related: Permitted; permitting.
permit (n.) Look up permit at Dictionary.com
"written statement of permission or license," 1714, from permit (v.).
permutate (v.) Look up permutate at Dictionary.com
1898 in modern use, "change the order of," from Latin permutatus, past participle of permutare (see permutation). "Probably regarded by those who use it as a back-formation from permutation" [OED]. Related: Permutated; permutating.
permutation (n.) Look up permutation at Dictionary.com
mid-14c., from Old French permutacion "change, shift" (14c.), from Latin permutationem (nominative permutatio) "a change, alteration, revolution," noun of action from past participle stem of permutare "change thoroughly, exchange," from per- "thoroughly" (see per) + mutare "to change" (see mutable).
permute (v.) Look up permute at Dictionary.com
late 14c., "to change one for another," from French permuter or directly from Latin permutare "to change thoroughly" (see permutation). Mathematical sense from 1878.
pernicious (adj.) Look up pernicious at Dictionary.com
early 15c., from Middle French pernicios (13c., Modern French pernicieux) and directly from Latin perniciosus "destructive," from pernicies "destruction, death, ruin," from per- "completely" (see per) + necis "violent death, murder," related to necare "to kill," nocere "to hurt, injure, harm," noxa "harm, injury" (see noxious). Related: Perniciously; perniciousness.
pernickety (adj.) Look up pernickety at Dictionary.com
1808 (pernicktie, in Jamieson), "precise, fastidious," extended form of Scottish pernicky, of uncertain origin, perhaps somehow from particular.
perorate (v.) Look up perorate at Dictionary.com
c.1600, back-formation from peroration, or else from Latin peroratus, past participle of perorare. Related: Perorated; perorating.
peroration (n.) Look up peroration at Dictionary.com
mid-15c., from Latin perorationem (nominative peroratio) "the ending of a speech or argument of a case," from past participle stem of perorare "argue a case to the end, bring a speech to a close," from per- "to the end" (see per) + orare "to speak, plead" (see orator).
peroxide (n.) Look up peroxide at Dictionary.com
1804, formed in English from per- "large amount" + oxide. Peroxide blonde is attested from 1918.
perp (n.) Look up perp at Dictionary.com
American English police slang shortening of perpetrator (as in perp walk); by 1940s.
perpendicular (adj.) Look up perpendicular at Dictionary.com
late 15c., from adverb (late 14c.), from Old French perpendiculer, from Latin perpendicularis "vertical, as a plumb line," from perpendiculum "plumb line," from perpendere "balance carefully," from per- "thoroughly" (see per) + pendere "to weigh, to hang" (see pendant). As a noun from 1570s. Related: Perpendicularly; perpendicularity.
perpensity (n.) Look up perpensity at Dictionary.com
"attention," 1704, from Latin perpensus "deliberate," past participle of perpendere "balance carefully" (see perpendicular) + -ity. Noted as obsolete by late 19c.
perpetrate (v.) Look up perpetrate at Dictionary.com
1540s, from Latin perpetratus, past participle of perpetrare "to perform, to accomplish," from per- "completely" + patrare "carry out," originally "bring into existence," from pater "father" (see father (n.)). Earlier in English was perpetren, mid-15c., from Old French perpetrer. Neither good nor bad in Latin, first used in English in statutes, hence its sense of "to perform criminally." Related: Perpetrated; perpetrating.
perpetration (n.) Look up perpetration at Dictionary.com
mid-15c., from Late Latin perpetrationem (nominative perpetratio) "an accomplishing, performing," noun of action from past participle stem of perpetrare "to perform, accomplish" (see perpetrate).
perpetrator (n.) Look up perpetrator at Dictionary.com
literally "the one who did it" (in English usually an evil act), 1560s, from Late Latin perpetrator, agent noun of perpetrare "to perform, to accomplish" (see perpetrate). Fem. forms are perpetratress (1811, of Nero's poisoner Locusta); perpetratrix (1862, in reference to Charlotte Corday).
perpetual (adj.) Look up perpetual at Dictionary.com
mid-14c., from Old French perpetuel "without end" (12c.) and directly from Latin perpetualis "universal," in Medieval Latin "permanent," from perpetuus "continuous, universal," from perpetis, genitive of Old Latin perpes "lasting," probably from per- "through" + root of petere "to seek, go to, aim at" (see petition (n.)). Related: Perpetually. Perpetual motion is attested from 1590s.
perpetuate (v.) Look up perpetuate at Dictionary.com
1520s, a back-formation from perpetuation or else from Latin perpetuatus, past participle of perpetuare "to make perpetual," from perpetuus (see perpetual). Related: Perpetuated; Perpetuating.
perpetuation (n.) Look up perpetuation at Dictionary.com
late 14c., from Medieval Latin perpetuationem (nominative perpetuatio), noun of action from past participle stem of perpetuare (see perpetuate).
perpetuity (n.) Look up perpetuity at Dictionary.com
late 14c., from Old French perpetuité "permanence, duration" (13c., Modern French perpétuité) and directly from Latin perpetuitatem (nominative perpetuitas) "uninterrupted duration, continuity, continuous succession," from perpetuus (see perpetual).
perpetuous (adj.) Look up perpetuous at Dictionary.com
"perpetual," 1610s, from Latin perpetuus "continuous, unbroken, uninterrupted" (see perpetual).
perplex (v.) Look up perplex at Dictionary.com
late 14c. as an adjective, "perplexed, puzzled, bewildered," from Latin perplexus "involved, confused, intricate;" but Latin had no corresponding verb *perplectere. The Latin compound would be per "through" (see per) + plexus "entangled," past participle of plectere "to twine, braid, fold" (see complex (adj.)).

The form of the English adjective shifted to perplexed by late 15c., probably to conform to other past participle adjectives. The verb is latest attested of the group, in 1590s, evidently a back-formation from the adjective. Related: Perplexing, which well describes the history of the word.
perplexed (adj.) Look up perplexed at Dictionary.com
late 15c., past participle adjective; see perplex. A case of a past participle form attested centuries before the verb (perplex isn't recorded until 17c.). Related: Perplexedly; perplexedness.
perplexity (n.) Look up perplexity at Dictionary.com
c.1300, "bewilderment," from Old French perplexite "confusion, perplexity," from Late Latin perplexitatem (nominative perplexitas), from Latin perplexus "confused, involved, interwoven," from per- "completely" + plexus "entangled," past participle of plectere "to twine" (see complex (adj.)). From 1590s as "something that causes perplexity."
perquisite (n.) Look up perquisite at Dictionary.com
mid-15c., "property acquired other than by inheritance," from Medieval Latin perquisitum "thing gained, profit," in classical Latin, "thing sought after," noun use of neuter past participle of perquirere "to seek, ask for," from per- "thoroughly" (see per) + quærere "to seek" (see query (v.)). For Latin vowel change, see acquisition. General meaning "fee or profit on top of regular wages" first recorded 1560s.
Perrier Look up Perrier at Dictionary.com
proprietary name of a natural mineral water from southern France, first attested in English 1904.
Perry Look up Perry at Dictionary.com
surname attested from late 12c., literally "dweller by the pear tree."