Lewis Short
(adjective) : invĭus, a, um, 2. in-via
* Without a road, impassable (syn.: inaccessus, devius; not in Cic. or Caes.).
* Lit.: lustra,Verg. A. 4, 151: longa via,id. ib. 3, 383: saltus,Liv. 9, 14: per invias atque ignotas rupes iter,id. 38, 2 fin.: saxa,Verg. A. 1, 537: maria Teucris,Verg. A. 9, 130: rupibus regio,Plin. 12, 14, 30, § 52: virtuti nulla est via,Ov. M. 14, 113.— Neutr.: nil virtuti invium,Tac. Agr. 27.— With inf.: Acheron invius renavigari,Sen. Herc. Fur. 715. — Subst.: invĭa, ōrum, n. plur., impassable places: per invia pleraque et errores,Liv. 21, 35: per vias inviaque,id. 23, 17: per vias, per invia,id. 38, 23: dumosa,Sil. 4, 305.
* Transf., inaccessible, impenetrable: regna,impenetrable,Verg. A. 6, 514: templa, Ov. M. 11, 414: tot bellis invia tecta,Sil. 14, 639: Sarmaticis lorica sagittis,Mart. 7, 2.
Charlton T. Lewis, Charles Short, A Latin Dictionary