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

ineffectual \in`effec"tual\ ?; 135, a.
   not producing the proper effect; without effect; inefficient;
   weak; useless; futile; unavailing; as, an ineffectual
   attempt; an ineffectual expedient. --pope.
   1913 webster

         the peony root has been much commended, . . . and yet
         has been by many found ineffectual.      --boyle.

   syn: inefficient; useless; inefficacious; vain; fruitless;
        unavailing; futile. see useless, inefficacious.
        1913 webster
see also:
useless inefficacious 

[2] : WordNet (r) 2.0

ineffectual
     adj 1: not sufficient to produce a desired result; "an ineffectual
            effort to block the legislation" ant: effectual
     2: not producing an intended effect; "an ineffective teacher";
        "ineffective legislation" syn: ineffective, uneffective
        ant: effective
     3: producing no result or effect; "a futile effort"; "the
        therapy was ineffectual"; "an otiose undertaking"; "an
        unavailing attempt" syn: futile, otiose, unavailing
     4: lacking in power or forcefulness; "an ineffectual ruler";
        "like an unable phoenix in hot ashes" syn: ineffective,
         unable
see also:
effectual ineffective uneffective effective futile otiose 
unavailing unable 

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

117 moby thesaurus words for "ineffectual":
   abortive, acarpous, aimless, arid, barren, bootless, borne,
   celibate, childless, counterproductive, desert, desolate, drained,
   dried-up, dry, effete, emasculate, empty, etiolated, exhausted,
   failed, failing, fallow, fatuitous, fatuous, featherweight,
   feckless, forceless, fruitless, futile, gaunt, gelded,
   ill-qualified, impotent, inadequate, inane, incapable, incompetent,
   ineffective, inefficacious, inefficient, infecund, infertile,
   inoperative, invalid, invertebrate, issueless, jejune, lame,
   leached, lightweight, limited, maladjusted, manque, mean,
   meaningless, menopausal, miscarried, miscarrying, narrow, no go,
   no-account, nonfertile, nonproducing, nonproductive, nonprolific,
   not equal to, not up to, nugacious, nugatory, of no account,
   of no effect, of no force, of no use, paltry, pointless, powerless,
   purposeless, set, sine prole, small, spineless, sterile, stickit,
   stillborn, successless, sucked dry, superfluous, teemless, unable,
   unadapted, unadjusted, unauthoritative, unavailable, unavailing,
   uncultivated, unequipped, unfertile, unfit, unfitted, unfortunate,
   unfruitful, unplowed, unproductive, unprolific, unqualified,
   unsown, unsuccessful, untilled, useless, vain, virgin, waste,
   wasted, weak, without any weight, without issue

Ineffectual >> I Words
Ineffectual, definition of term: Ineffectual
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