Lewis Short
(adjective) : terrĭfĭcus, a, um, terreo-facio
* That causes terror, frightful, terrific (poet.): (Curetes) cristae,Lucr. 2, 632; 5, 1314: caesaries capitis,Ov. M. 1, 179: vates,Verg. A. 5, 524: sacrum,Val. Fl. 1, 785: vaticinationes,Plin. Ep. 6, 20, 19.
Charlton T. Lewis, Charles Short, A Latin Dictionary