inviolable vs unattackable

inviolable and unattackable both are adjectives.

Word	Noun	Adjective	Verb	Adverb
inviolable	No	Yes	No	No
unattackable	No	Yes	No	No

As adjectives, inviolable and unattackable are synonyms defined as:

inviolable and unattackable: immune to attack; incapable of being tampered with

Other synonyms of inviolable include impregnable, secure, strong, unassailable.

inviolable (adjective)	unattackable (adjective)
incapable of being transgressed or dishonored	immune to attack; incapable of being tampered with
not capable of being violated or infringed
immune to attack; incapable of being tampered with
must be kept sacred