perfidious

per·fid·i·ous
P3E1R1F4I1D2I1O1U1S1
US/pɚˈfɪdi.əs/UK/pəˈfɪdi.əs/

adjective

Of, pertaining to, or representing perfidy; disloyal to what should command one's fidelity or allegiance.

UncommonFirst used late 16th c.Scrabble 16

Meanings

adjectiveperfidious (comparative more perfidious, superlative most perfidious)

comparative more perfidious · superlative most perfidious

  1. Of, pertaining to, or representing perfidy; disloyal to what should command one's fidelity or allegiance.First known use late 16th c.

    [S]he knew Huntly for the ambitious traitor he was, a man peculiarly perfidious and self-seeking.

    1905, Andrew Lang, “ch. 14”, in John Knox and the Reformation
    4 more examples

    TRINCULO (speaking about Caliban): By this light, a most perfidious and drunken / monster: when his god's asleep, he'll rob his bottle.

    1610–1611 (date written), William Shakespeare, “The Tempest”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act II, scene ii]

    The perfidious Ricimer soon became dissatisfied with Anthe'mius, and raised the standard of revolt.

    1851, Oliver Goldsmith, “ch. 26”, in William C. Taylor, editor, Dr. Goldsmith's History of Rome

    When the Nazis branded Feininger a "degenerate artist" in 1937, he left 54 paintings for safekeeping with a Bauhaus friend named Hermann Klumpp. After the war, and for the rest of Feininger's life, the perfidious Klumpp refused to give them back.

    2005 June 21, “Art: The Velocipede of Modernism”, in Time, archived from the original on 12 Nov 2011

    Enraged, the 2010 Nobel literature laureate thundered that he was “flabbergasted to learn that this kind of gossip can find its way into a respectable publication such as the Book Review” - a “slanderous and perfidious” instance of the convergence of posh and pop that his book inveighs against.

    2015 August 28, John Dugdale, “Mario Vargas Llosa, Hola! and the shallow reading of a review”, in The Guardian, →ISSN

    Synonyms: deceitful, disloyal, duplicitous, faithless, treacherous, traitorous, unfaithful

Synonyms & antonyms

adjectiveOf, pertaining to, or representing perfidy; disloyal to what should command one's fidelity or allegiance.

More synonyms by meaning

adjectivetending to betray; especially having a treacherous character as attributed to the Carthaginians by the Romans

Synonym sets from Open English WordNet, CC BY 4.0.

Origin

  1. Proto-Indo-European*per-der.?
  2. Proto-Indo-European*pér
  3. Proto-Italic*per
  4. Latinper
  5. Proto-Indo-European*bʰeydʰ-
  6. Latinfidēs
  7. Latinperfidus
  8. Latinperfidia
  9. Proto-Indo-European*h₃ed-
  10. Proto-Indo-European*h₃édosder.?
  11. Latinperfidiōsus
  12. Englishperfidious

From Latin perfidiōsus (“treacherous”), from perfidia. By surface analysis, perfidy + -ous.

Full word history & related roots →

Translations

Bulgarian коварен, вероломен
  • коварен (kovaren)pertaining to perfidy
  • вероломен (verolomen)pertaining to perfidy
  • предателски (predatelski)pertaining to perfidy
Chinese Mandarin 背信棄義的 /背信弃义的
  • 背信棄義的 /背信弃义的 (bèixìnqìyì de)pertaining to perfidy
Dutch verraderlijk, perfide
  • verraderlijkpertaining to perfidy
  • perfidepertaining to perfidy
  • doortraptpertaining to perfidy
Finnish petollinen
  • petollinenpertaining to perfidy
French perfide
  • perfidepertaining to perfidy
German perfide
  • perfidepertaining to perfidy
Greek παράσπονδος
  • παράσπονδος (paráspondos)pertaining to perfidy
Hungarian hitszegő, álnok
  • hitszegőpertaining to perfidy
  • álnokpertaining to perfidy
  • csalárdpertaining to perfidy
  • árulópertaining to perfidy
  • szószegőpertaining to perfidy
  • alattomospertaining to perfidy
  • perfidpertaining to perfidy
  • galádpertaining to perfidy
  • alávalópertaining to perfidy
  • aljaspertaining to perfidy
  • hitványpertaining to perfidy
Irish fealltach
  • fealltachpertaining to perfidy
Latin perfidus
  • perfiduspertaining to perfidy
Portuguese pérfido, desleal
  • pérfidopertaining to perfidy
  • deslealpertaining to perfidy
Russian вероло́мный, преда́тельский
  • вероло́мный (verolómnyj)pertaining to perfidy
  • преда́тельский (predátelʹskij)pertaining to perfidy
  • кова́рный (kovárnyj)pertaining to perfidy
Spanish pérfido
  • pérfidopertaining to perfidy
Turkish hain, kalleş
  • hainpertaining to perfidy
  • kalleşpertaining to perfidy
Ukrainian віроломний, зрадливий
  • віроломний (virolomnyj)pertaining to perfidy
  • зрадливий (zradlyvyj)pertaining to perfidy

Rhymes & wordplay

Rhymes with perfidious

All rhymes →
Cite this entry
APA

perfidious. (n.d.). In WatkinsX Dictionary. Retrieved November 3, 2026, from https://dictionary.watkinsx.com/word/perfidious

MLA

“perfidious.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/perfidious. Accessed November 3, 2026.

Chicago

WatkinsX Dictionary, s.v. “perfidious,” accessed November 3, 2026, https://dictionary.watkinsx.com/word/perfidious.

Source: perfidious on Wiktionary, CC BY-SA 4.0.