[1] : The Collaborative International Dictionary of English v.0.48

unshakable \unshak"able\, a.
   not capable of being shaken; firm; fixed. --shak. j. s. mill.
   1913 webster

[2] : WordNet (r) 2.0

unshakable
     adj 1: marked by firm determination or resolution; not shakable;
            "firm convictions"; "a firm mouth"; "steadfast
            resolve"; "a man of unbendable perseverence";
            "unwavering loyalty" syn: firm, steadfast, steady,
             unbendable, unfaltering, unwavering
     2: without flaws or loopholes; "an ironclad contract"; "a
        watertight alibi"; "a bulletproof argument" syn: ironclad,
         unassailable, watertight, bulletproof
see also:
firm steadfast steady unbendable unfaltering unwavering 
ironclad unassailable watertight bulletproof 

[3] : Moby Thesaurus II by Grady Ward, 1.0

24 moby thesaurus words for "unshakable":
   abiding, balanced, cool, fast, fiducial, firm, firm as gibraltar,
   fixed, imperturbable, in equilibrium, predictable, reliable,
   secure, solid, sound, stable, steadfast, steady, substantial,
   unflappable, unflinching, unwavering, well-balanced,
   without nerves

Unshakable >> U Words
Unshakable, definition of term: Unshakable
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