Lewis & Short

falsĭlŏquus (-locus), a, um, adj. [falsus + loquor], that speaks falsehoods: quarum rerum te falsilocum mihi esse nolo. Plaut. Capt. 2, 2, 14; Prud. Apoth. 107; also Plaut. Mil. 2, 2, 36, glossema.
Subst.: fal-sĭlŏquus, i, m., a false accuser, Vulg. Job, 16, 9.