vānĭdĭcus — Lewis & Short
vānĭdĭcus, a, um, adj.vanus-dico,
I vain - speaking; false - speaking; subst., a liar (ante- and post-class. and rare):
cum probis potius quam cum improbis vivere vanidicis,Plaut. Trin. 2, 1, 37; Amm. 16, 7, 2.