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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


[menˈdeɪʃəs] ADJ (frm) → mendaz


References in classic literature ?
" answered I, "that is a kind of state, and indeed the most mendacious.
Yes--what the mendacious family chronicles call extinct in the male line--that is, gone down--gone under.
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.