Synonyms of unshakable

Adjective

1. firm, steadfast, steady, stiff, unbendable, unfaltering, unshakable, unwavering, resolute (vs. irresolute)

usage: marked by firm determination or resolution; not shakable; "firm convictions"; "a firm mouth"; "steadfast resolve"; "a man of unbendable perseverence"; "unwavering loyalty"

2. unassailable, unshakable, watertight, bulletproof, incontestable (vs. contestable), incontestible

usage: without flaws or loopholes; "an ironclad contract"; "a watertight alibi"; "a bulletproof argument"