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1. Lying; untruthful: a mendacious child.
2. False; untrue: a mendacious statement. See Synonyms at dishonest.

[From Latin mendācium, lie, from mendāx, mendāc-, mendacious.]

men·da′cious·ly adv.


(mɛnˈdeɪ ʃəs)

1. telling lies, esp. habitually; dishonest.
2. false or untrue: a mendacious report.
[1610–20; < Latin mendāx; see -acious]
men•da′cious•ly, adv.
men•da′cious•ness, n.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.mendacious - given to lying; "a mendacious child"
untruthful - not expressing or given to expressing the truth; "the statement given under oath was untruthful"; "an untruthful person"
2.mendacious - intentionally untrue; "a mendacious statement"
false - not in accordance with the fact or reality or actuality; "gave false testimony under oath"; "false tales of bravery"


adjective lying, false, untrue, fraudulent, dishonest, deceptive, deceitful, insincere, duplicitous, perjured, perfidious, fallacious, untruthful politicians issuing mendacious claims and counter-claims
true, genuine, honest, truthful


Given to or marked by deliberate concealment or misrepresentation of the truth:


[menˈdeɪʃəs] ADJ (frm) → mendaz


References in classic literature ?
Yes--what the mendacious family chronicles call extinct in the male line--that is, gone down--gone under.
The mendacious captain was perfectly well aware that an affair of honor always makes a man stand well in the eyes of a woman.
Mildred had become great friends with her and had given her an elaborate but mendacious account of the circumstances which had brought her to the pass she was in.
Alexander I- the pacifier of Europe, the man who from his early years had striven only for his people's welfare, the originator of the liberal innovations in his fatherland- now that he seemed to possess the utmost power and therefore to have the possibility of bringing about the welfare of his peoples- at the time when Napoleon in exile was drawing up childish and mendacious plans of how he would have made mankind happy had he retained power- Alexander I, having fulfilled his mission and feeling the hand of God upon him, suddenly recognizes the insignificance of that supposed power, turns away from it, and gives it into the hands of contemptible men whom he despises, saying only:
At the most, I regard thee as the ventriloquist of the earth: and ever, when I have heard subversive and spouting devils speak, I have found them like thee: embittered, mendacious, and shallow.
answered I, "that is a kind of state, and indeed the most mendacious.
And she followed it with the everlasting plaint of the poor, pathetically mendacious, miserably authenticated by the horrible breath of cheap rum and soap-suds.
To the morality of a Western reader an account of these meetings would wear perhaps the sinister character of old legendary tales where the Enemy of Mankind is represented holding subtly mendacious dialogues with some tempted soul.
She launched an extraordinarily mendacious attack on the Holy Land Principles resolution that was presented at the meeting.
Bill takes writing tips from Christopher Marlowe, a marvellously morose and mendacious Jim Howick.
His utter failure in this regard owes him to tender an apology to the nation for his mendacious and willful claims in order to get votes from the electorates, he added.
Netanyahu gave a particularly mendacious reason when he said that "given the deteriorating situation in the Middle East, one must act responsibly and with due consideration alongside a determined struggle against extremists.