Lewis Short
(adjective) : pĕnĕtrābĭlis, e, penetro.
* Pass., that can be pierced or penetrated, penetrable (poet. and in post-Aug. prose): corpus nullo penetrabile telo,Ov. M. 12, 166: cum sit nulli penetrabilis,Sen. Const. Sap. 3: pectus ferro,Stat. Th. 2, 653: terra,Just. 4, 1, 2: caput haud penetrabile Nili,inaccessible,Stat. S. 3, 5, 21.
* Act., piercing, penetrating (poet. and in post-class. prose): Boreae penetrabile frigus,Verg. G. 1, 93: telum,id. A. 10, 481: harundo,Sil. 7, 649: fulmen,Ov. M. 13, 857: vinum penetrabilius in venas,Macr. 7, 12: querimonia,Gell. 10, 3, 4.—Comp.: sermo Dei est penetrabilior omni gladio ancipiti,Vulg. Heb. 4, 12.
* = penetralis (late Lat.): ad regni penetrabilia, Laurent. Hom. 1.
Charlton T. Lewis, Charles Short, A Latin Dictionary