12c., froward, fraward "turned against, perverse, disobedient; peevish, petulant; adverse, difficult," as a preposition, "away from," the Northern form of Old English fromweard (see fromward), with Old Norse fra (see fro) in place of English from. Opposite of toward, it renders Latin pervertus in early translations of the Psalms, and also meant "about to depart, departing," and "doomed to die." Related: Frowardly; frowardness.

"through, by means of," 1580s (earlier in various Latin and French phrases, in the latter often par), from Latin per "through, during, by means of, on account of, as in," from PIE root *per- (1) "forward," hence "through, in front of, before, first, chief, toward, near, around, against."

late 14c., in Bible translations, "corrupted, false, turned from the right way," past-participle adjective from pervert (v.). With an implied sexual sense by 1897.

late 14c., peyvesshe "perverse, capricious, silly," a word of uncertain origin; probably modeled on Latin perversus "reversed, perverse," past participle of pervertere "to turn about" (see pervert (v.)). Original sense was obsolete from 17c. The meaning "cross, fretful. ill-tempered" is recorded from 1520s. Related: Peevishly; peevishness.

also perve, "a sexual pervert," 1944, slang shortening of (sexual) pervert (n.). As a slang verb, by 1941 as "to act erotically" (intransitive), by 1959 as "to eroticize" something (transitive).

late 14c., "wicked," from Old French pervers "unnatural, degenerate; perverse, contrary" (12c.) and directly from Latin perversus "turned away, contrary, askew," figuratively, "turned away from what is right, wrong, malicious, spiteful," past participle of pervertere "to corrupt" (see pervert (v.)).

The Latin word is glossed in Old English by forcerred, from past participle of forcyrran "to avoid," from cierran "to turn, return." The meaning "wrong, not in accord with what is accepted or standard, turned away from what is right" is from 1560s; the sense of "obstinate in the wrong, stubborn" is from 1570s. It keeps the non-sexual senses of pervert (v.) and allows the psychological ones to go with perverted. Related: Perversely; perverseness.

Perverse has reference to one's attitude, in both conduct and opinion. The perverse person is settled in habit and disposition of contrariness; he not only likes or dislikes, acts or refuses to act, by the rule of contradiction to the wishes, commands, or opinions of others, especially of those whom he ought to consider, but be is likely even to take pains to do or say that which he knows to be offensive or painful to them. Perversity may be found in a child, but it is so settled an element of character as to be rather the mark of an adult. [Century Dictionary]

late 14c., "action of turning aside from truth; corruption, distortion" (originally of religious beliefs), from Latin perversionem (nominative perversio) "a turning about," noun of action from past-participle stem of pervertere (see pervert (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.

Perversions are defined as unnatural acts, acts contrary to nature, bestial, abominable, and detestable. Such laws are interpretable only in accordance with the ancient tradition of the English common law which ... is committed to the doctrine that no sexual activity is justifiable unless its objective is procreation. [A.C. Kinsey, et.al., "Sexual Behavior in the Human Male," 1948]

Proto-Indo-European root forming words meaning "to turn, bend."

It forms all or part of: adverse; anniversary; avert; awry; controversy; converge; converse (adj.) "exact opposite;" convert; diverge; divert; evert; extroversion; extrovert; gaiter; introrse; introvert; invert; inward; malversation; obverse; peevish; pervert; prose; raphe; reverberate; revert; rhabdomancy; rhapsody; rhombus; ribald; sinistrorse; stalwart; subvert; tergiversate; transverse; universe; verbena; verge (v.1) "tend, incline;" vermeil; vermicelli; vermicular; vermiform; vermin; versatile; verse (n.) "poetry;" version; verst; versus; vertebra; vertex; vertigo; vervain; vortex; -ward; warp; weird; worm; worry; worth (adj.) "significant, valuable, of value;" worth (v.) "to come to be;" wrangle; wrap; wrath; wreath; wrench; wrest; wrestle; wriggle; wring; wrinkle; wrist; writhe; wrong; wroth; wry.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit vartate "turns round, rolls;" Avestan varet- "to turn;" Hittite hurki- "wheel;" Greek rhatane "stirrer, ladle;" Latin vertere (frequentative versare) "to turn, turn back, be turned; convert, transform, translate; be changed," versus "turned toward or against;" Old Church Slavonic vrŭteti "to turn, roll," Russian vreteno "spindle, distaff;" Lithuanian verčiu, versti "to turn;" German werden, Old English weorðan "to become;" Old English -weard "toward," originally "turned toward," weorthan "to befall," wyrd "fate, destiny," literally "what befalls one;" Welsh gwerthyd "spindle, distaff;" Old Irish frith "against."

Proto-Indo-European root forming prepositions, etc., meaning "forward," and, by extension, "in front of, before, first, chief, toward, near, against," etc.

It forms all or part of: afford; approach; appropriate; approve; approximate; barbican; before; deprive; expropriate; far; first; for; for-; fore; fore-; forefather; foremost; former (adj.); forth; frame; frau; fret; Freya; fro; froward; from; furnish; furniture; further; galore; hysteron-proteron; impervious; improbity; impromptu; improve; palfrey; par (prep.); para- (1) "alongside, beyond; altered; contrary; irregular, abnormal;" paradise; pardon; paramount; paramour; parvenu; pellucid; per; per-; percent; percussion; perennial; perestroika; perfect; perfidy; perform; perfume; perfunctory; perhaps; peri-; perish; perjury; permanent; permeate; permit; pernicious; perpendicular; perpetual; perplex; persecute; persevere; perspective; perspire; persuasion; pertain; peruse; pervade; pervert; pierce; portray; postprandial; prae-; Prakrit; pre-; premier; presbyter; Presbyterian; preterite; pride; priest; primal; primary; primate; primavera; prime; primeval; primitive; primo; primogenitor; primogeniture; primordial; primus; prince; principal; principle; prior; pristine; private; privilege; privy; pro (n.2) "a consideration or argument in favor;" pro-; probably; probe; probity; problem; proceed; proclaim; prodigal; produce; profane; profess; profile; profit; profound; profuse; project; promise; prompt; prone; proof; proper; property; propinquity; prophet; prose; prostate; prosthesis; protagonist; Protean; protect; protein; Proterozoic; protest; proto-; protocol; proton; protoplasm; Protozoa; proud; prove; proverb; provide; provoke; prow; prowess; proximate; Purana; purchase; purdah; reciprocal; rapprochement; reproach; reprove; veneer.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit pari "around, about, through," parah "farther, remote, ulterior," pura "formerly, before," pra- "before, forward, forth;" Avestan pairi- "around," paro "before;" Hittite para "outside of," Greek peri "around, about, near, beyond," pera "across, beyond," paros "before," para "from beside, beyond," pro "before;" Latin pro "before, for, on behalf of, instead of," porro "forward," prae "before," per "through;" Old Church Slavonic pra-dedu "great-grandfather;" Russian pere- "through;" Lithuanian per "through;" Old Irish ire "farther," roar "enough;" Gothic faura "before," Old English fore (prep.) "before, in front of," (adv.) "before, previously," fram "forward, from," feor "to a great distance, long ago;" German vor "before, in front of;" Old Irish air- Gothic fair-, German ver-, Old English fer-, intensive prefixes.