I.given to lying, mendacious; subst., a liar.
I. Lit.: “mendacem esse adversus aliquem,” Plaut. Poen. 1, 2, 188: “cum mendaci homini, ne verum quidem dicenti, credere soleamus,” Cic. Div. 2, 71, 146: “Carthaginienses fraudulenti et mendaces,” id. Agr. 2, 35, 95: “aretalogus,” Juv. 15, 16.—As subst.: mendax , dācis, m., a liar.—Prov.: “mendacem memorem esse oportet,” a liar should have a good memory, Quint. 4, 2, 91.— Comp.: “Parthis mendacior,” Hor. Ep 2, 1, 112.—Sup.: “mendacissimus,” the greatest liar, Plaut. Rud. 3, 4, 48.—With gen.: “si hujus rei me mendacem esse inveneris,” Plaut. As. 5, 2, 4.—With dat.: “saepe fui mendax pro te mihi,” Ov. H. 2, 11.—With in and acc.: “in parentem,” Hor. C. 3, 11, 35; for which adversum, Plaut. Poen. 1, 2, 188.— With in and abl.: “in tenui farragine,” Pers. 5, 77.—
II. Transf., of inanim, and abstr. things, lying, false, deceptive; feigned, fictitious, counterfeit, not real, etc. (mostly poet.): “mendacia visa,” Cic. Div. 2, 62, 127: “speculum,” Ov. Tr. 3, 7, 38: “fundus,” that does not yield the expected fruits, Hor. C. 3, 1, 30: “damnum,” Ov. A. A. 1, 431: “infamia,” Hor. Ep. 1, 16, 39: “os,” Tib. 3, 6, 35: “pennae,” Ov. M. 10, 159: “quidquid Graecia mendax audet in historia,” Juv. 10, 174.—Hence, adv.: mendācĭter , falsely, mendaciously (post-class.): “praedicare,” Sol. 1, 87.— Sup.: “mendacissime dicere,” Aug. Mor. Eccl. 1, 17.