Adjective unshakable has 2 senses
- firm, steadfast, steady, unbendable, unfaltering, unshakable, unwavering - marked by firm determination or resolution; not shakable; "firm convictions"; "a firm mouth"; "steadfast resolve"; "a man of unbendable perseverence"; "unwavering loyalty"
Antonym: irresolute (indirect, via resolute)
- ironclad, unassailable, unshakable, watertight, bulletproof - without flaws or loopholes; "an ironclad contract"; "a watertight alibi"; "a bulletproof argument"
Antonym: contestable (indirect, via incontestable)
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