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

powerless \pow"erless\, a.
   destitute of power, force, or energy; weak; impotent; not
   able to produce any effect. -- pow"erlessly, adv. --
   pow"erlessness, n.
   1913 webster
see also:
pow"erlessly pow"erlessness 

[2] : WordNet (r) 2.0

powerless
     adj : lacking power syn: weak ant: powerful
see also:
weak powerful 

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

67 moby thesaurus words for "powerless":
   anemic, asthenic, bloodless, chicken, cowardly, crippled,
   debilitated, decrepit, disabled, drooping, droopy, dull, effete,
   etiolated, faint, faintish, featherweight, feeble, flabby, flaccid,
   floppy, forceless, gone, gutless, helpless, imbecile, impotent,
   inactive, incapable, incapacitated, incompetent, ineffective,
   ineffectual, inefficacious, inert, infirm, languid, languorous,
   lightweight, limber, limp, listless, lustless, marrowless,
   nerveless, no-account, of no account, passive, pithless, pooped,
   rubbery, sapless, sinewless, slack, soft, spineless, strengthless,
   supine, unable, unauthoritative, unfit, unhardened, unnerved,
   unstrung, weak, weakly, without any weight

Powerless >> P Words
Powerless, definition of term: Powerless
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