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mendācĭlŏquus, a, um, adj. [mendacium-loquor], false-speaking, lying, mendacious (ante- and post-class.): nihil est stolidius, Neque mendaciloquius, Plaut. Trin. 1, 2, 163.
As subst.: mendācĭlŏquus, i, m., a liar: mendaciloquorum doctrinae, Tert. adv. Psych. 2.