inviolable in WordNet English dictionary

1. not capable of being violated or infringed
   "infrangible human rights"
   absolute  infrangible  inviolable 
   
2. immune to attack; incapable of being tampered with
   "an impregnable fortress"; "fortifications that made the frontier inviolable"; "a secure telephone connection"
   impregnable  inviolable  secure  strong  unassailable  unattackable 
   
3. incapable of being transgressed or dishonored
   "the person of the king is inviolable"; "an inviolable oath"
   inviolable 
   
4. must be kept sacred
   inviolable  inviolate  sacrosanct