mendacious

M3E1N1D2A1C3I1O1U1S1
/mɛnˈdeɪʃəs/

adjective

Lying, untruthful or dishonest.

“utterly mendacious”

Similar
bastardcounterfactualerroneousfallaciousfalseoffcounterfeitfictitious
OriginMiddle French mendacieux ← Latin mendācium →
UncommonScrabble 15
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Meanings

adjectivemendacious (comparative more mendacious, superlative most mendacious)

comparative more mendacious · superlative most mendacious

  1. Lying, untruthful or dishonest.

    He was dismissed as a mendacious witness.

  2. etcFalse or untrue.

    utterly mendacious

    2 more examples

    mendacious propaganda

    The report was filled with mendacious claims.

    Synonyms: bastard, counterfactual, erroneous, fallacious, false, off, counterfeit, fictitious

Synonyms & antonyms

adjectiveFalse or untrue.

Similar
bastardcounterfactualerroneousfallaciousfalseoffcounterfeitfictitiousinaccurateincorrectinventedmade upnonfactualnontruenontruthfulpseudo-spuriousuntrueuntruthfulunveracious

More synonyms by meaning

adjectivegiven to lying

Similar
untruthful

adjectiveintentionally untrue

Similar
false
Also see
corrupteddeceptivedouble-dealingdouble-faceddoubleheartedfallaciousfalseguiledguilefulhollow-heartedjanus-facedswiketreacherousuntruthful

Synonym sets from Open English WordNet, CC BY 4.0.

Origin

  1. Latinmendācium“lie, untruth”
  2. Middle Frenchmendacieux
  3. Englishmendacious

Borrowed from Middle French mendacieux, from Latin mendācium (“lie, untruth”), from mendāx (“lying”), + -ious.

More words from Middle French, Latin

Full word history & related roots →

Translations

Afrikaans leunagtig, oneerlik
  • leunagtiglying, untruthful or dishonest
  • oneerliklying, untruthful or dishonest
  • liegendlying, untruthful or dishonest
Ancient Greek ψευδολόγος
  • ψευδολόγος (pseudológos)lying, untruthful or dishonest
Arabic كَاذِب
  • كَاذِب (kāḏib)lying, untruthful or dishonest
Bulgarian лъжлив
  • лъжлив (lăžliv)lying, untruthful or dishonest
Catalan mentider
  • mentiderlying, untruthful or dishonest
Chinese Mandarin 說謊的 /说谎的
  • 說謊的 /说谎的 (shuōhuǎng de)lying, untruthful or dishonest
Czech prolhaný
  • prolhanýlying, untruthful or dishonest
Dutch leugenachtig, oneerlijk
  • leugenachtiglying, untruthful or dishonest
  • oneerlijklying, untruthful or dishonest
  • liegendlying, untruthful or dishonest
Finnish valheellinen
  • valheellinenlying, untruthful or dishonest
French fallacieux, mensonger
  • fallacieuxlying, untruthful or dishonest
  • mensongerlying, untruthful or dishonest
  • trompeurlying, untruthful or dishonest
German lügnerisch, verlogen
  • lügnerischlying, untruthful or dishonest
  • verlogenlying, untruthful or dishonest
  • unwahrlying, untruthful or dishonest
Greek αναληθής
  • αναληθής (analithís)lying, untruthful or dishonest
Hebrew שקרן, לא ישר
  • שקרןlying, untruthful or dishonest
  • לא ישרlying, untruthful or dishonest
Hungarian hazug, hazudozó
  • hazuglying, untruthful or dishonest
  • hazudozólying, untruthful or dishonest
Irish bréagach
  • bréagachlying, untruthful or dishonest
Italian mendace, menzognero
  • mendacelying, untruthful or dishonest
  • menzognerolying, untruthful or dishonest
  • bugiardolying, untruthful or dishonest
Japanese 虚偽の, 不正直
  • 虚偽の (kyogi no)lying, untruthful or dishonest
  • 不正直 (fushōjiki)lying, untruthful or dishonest
Latin mendax
  • mendaxlying, untruthful or dishonest
Norwegian Bokmål løgnaktig
  • løgnaktiglying, untruthful or dishonest
Polish zakłamany, kłamliwy
  • zakłamanylying, untruthful or dishonest
  • kłamliwylying, untruthful or dishonest
Portuguese mentiroso, mendaz
  • mentirosolying, untruthful or dishonest
  • mendazlying, untruthful or dishonest
Romanian mincinos
  • mincinoslying, untruthful or dishonest
Russian лжи́вый
  • лжи́вый (lžívyj)lying, untruthful or dishonest
Spanish mentiroso, embustero
  • mentirosolying, untruthful or dishonest
  • embusterolying, untruthful or dishonest
  • mendazlying, untruthful or dishonest
  • mendigolying, untruthful or dishonest
  • mendigalying, untruthful or dishonest
Swedish lögnaktig, förljugen
  • lögnaktiglying, untruthful or dishonest
  • förljugenlying, untruthful or dishonest
Ukrainian брехли́вий
  • брехли́вий (brexlývyj)lying, untruthful or dishonest
Welsh celwyddog
  • celwyddoglying, untruthful or dishonest

Rhymes & wordplay

Rhymes with mendacious

spacioustenaciousgraciousgaseouscretaceousherbaceousaudaciousefficaciousvoraciousvivaciousfallaciouscarbonaceoussebaceousvexatiousflirtatiouscurvaceousostentatioussalaciousrapaciouscapacioussagaciouspugnaciousloquaciousungracious
All rhymes →
Cite this entry
APA

mendacious. (n.d.). In WatkinsX Dictionary. Retrieved November 2, 2026, from https://dictionary.watkinsx.com/word/mendacious

MLA

“mendacious.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/mendacious. Accessed November 2, 2026.

Chicago

WatkinsX Dictionary, s.v. “mendacious,” accessed November 2, 2026, https://dictionary.watkinsx.com/word/mendacious.

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