Mendacity \Men*dac"i*ty\, n.; pl. {Mendacities}. [L. mendacitas.] 1. The quality or state of being mendacious; a habit of lying. --Macaulay. [1913 Webster] 2. A falsehood; a lie. --Sir T. Browne. [1913 Webster] Syn: Lying; deceit; untruth; falsehood. [1913 Webster]