Unassailable (Adjective)
Meaning 1
Without flaws or loopholes; "an ironclad contract"; "a watertight alibi"; "a bulletproof argument".
Classification
All adjective clusters.
Synonyms
Meaning 3
Immune to attack; incapable of being tampered with; "an impregnable fortress"; "fortifications that made the frontier inviolable"; "a secure telephone connection".
Classification
All adjective clusters.