WordNet: impregnable, inviolable, secure, strong, unassailable, unattackable

Sanatista
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

  • (suomi) vahva (synonyymi)


unassailable


unattackable