invulnerabilityn.

1775 in J. Ash New Dict. Eng. Lang.

1831 T. Carlyle in Westm. Rev. July 11 His Hornedness meant only an Invulnerability.

1881 Times 23 Apr. 6/5 The practical invulnerability of the armour.

1900 Daily News 4 Sept. 6/1 The superstition of their [sc. the Boxers'] invulnerability to cannon shot... The Empress-Dowager..is said to have been deceived by the invulnerability superstition.

1962 Listener 29 Mar. 540/1 ‘Invulnerability’ suggests, first of all, protecting your missiles under concrete, or hiding missiles and bombers and submarines by having them moving about. But ‘invulnerability’ also includes having too many missile sites for your enemy to be able to knock out even with a perfectly executed first strike; it includes having a mixed deterrent of bombers and land-base missiles and sea-going missiles, and it includes the case where your enemy knows that you are sure to have enough warning to launch your missiles and get your bombers aloft. This business of warning introduces serious ambiguities in the idea of ‘invulnerability’.

1972 Sci. Amer. July 14/2 As a result of this possibility each country will be concerned to maintain the invulnerability of its submarine-based strategic missiles, which are essentially immune to attack from land-based weapons.