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

unable \una"ble\, a.
   not able; not having sufficient strength, means, knowledge,
   skill, or the like; impotent; weak; helpless; incapable; --
   now usually followed by an infinitive or an adverbial phrase;
   as, unable for work; unable to bear fatigue.
   1913 webster

         sapless age and weak unable limbs.       --shak.
   1913 webster

[2] : WordNet (r) 2.0

unable
     adj 1: usually followed by `to' not having the necessary means or
            skill or know-how; "unable to get to town without a
            car"; "unable to obtain funds" syn: not able ant:
             able
     2: usually followed by `to' lacking necessary physical or
        mental ability; "dyslexics are unable to learn to read
        adequately"; "the sun was unable to melt enough snow"
        syn: unablep
     3: lacking in power or forcefulness; "an ineffectual ruler";
        "like an unable phoenix in hot ashes" syn: ineffective,
         ineffectual
see also:
not able able unablep ineffective ineffectual 

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

25 moby thesaurus words for "unable":
   ill-qualified, impotent, inadequate, incapable, incapable of,
   incompetent, ineffective, ineffectual, inefficient, inept,
   inferior, maladjusted, not equal to, not up to, powerless,
   unable to, unadapted, unadjusted, unendowed, unequipped, unfit,
   unfitted, ungifted, unqualified, untalented

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