Lewis Short
(adjective) : horrĭfer, ĕra, ĕrum (archaic
* Gen. plur. horriferum, Pac. ap. Cic. Or. 46, 155), horror-fero, that brings trembling or terror, terrible, dreadful, horrible, horrific (poet.): unde horrifer Aquiloni' stridor gelidas molitur nives, Att. ap. Cic. Tusc. 1, 28, 68: Boreas,Ov. M. 1, 65; 15, 471: axis,Val. Fl. 5, 518: nix,id. 5, 307: prodigium horriferum, Pac. ap. Cic. Or. 46, 155: aestus (Tartari),Lucr. 3, 1012: Aegis (= δεινή, Hom.), Verg. A. 8, 435: Erinys,Ov. M. 1, 725: voces,Lucr. 5, 996.
Charlton T. Lewis, Charles Short, A Latin Dictionary