Source : Webster's Revised Unabridged Dictionary (1913)

Mendacious \Men*da"cious\, a. [L. mendax, -acis, lying, cf.
   mentiri to lie.]
   1. Given to deception or falsehood; lying; as, a mendacious
      person.

   2. False; counterfeit; containing falsehood; as, a mendacious
      statement. -- {Men*da"cious*ly}, adv. --
      {Men*da"cious*ness}, n.