INEXPUGNABLE

impregnable, inexpugnable

(adjective) incapable of being overcome, challenged or refuted; “an impregnable argument”; “impregnable self-confidence”

Source: WordNet® 3.1

Etymology

Adjective

inexpugnable (comparative more inexpugnable, superlative most inexpugnable)

Impossible to eliminate or destroy; impregnable.

Anagrams

• inexpungable

Source: Wiktionary

In`ex*pug"na*ble, a. Etym: [L. inexpugnabilis: cf. F. inexpugnable. See In- not, and Expugnable.]

Definition: Incapable of being subdued by force; impregnable; unconquerable. Burke. A fortress, inexpugnable by the arts of war. Milman.

Source: Webster’s Unabridged Dictionary 1913 Edition