The quality of being impenetrable (by people or light or missiles etc.).

synonym: impenetrability.

Roget 261: closure, occlusion, blockade; shutting up etc. v.; obstruction etc. (hindrance) 706; embolus; contraction etc. 195; infarction; constipation, obstipation^†; blind alley, blind corner; keddah^†; cul-de-sac, caecum; imperforation^†, imperviousness etc. adj.; impermeability; stopper etc. 263.    ... show more

Polish: niepoznawalność