The Collaborative International Dictionary of English v.0.48:

Helpless \Help"less\, a.
   1. Destitute of help or strength; unable to help or defend
      one's self; needing help; feeble; weak; as, a helpless
      infant.
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            How shall I then your helpless fame defend? --Pope.
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   2. Beyond help; irremediable.
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            Some helpless disagreement or dislike, either of
            mind or body.                         --Milton.
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   3. Bringing no help; unaiding. [Obs.]
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            Yet since the gods have been
            Helpless foreseers of my plagues.     --Chapman.
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   4. Unsupplied; destitute; -- with of. [R.]
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            Helpless of all that human wants require. --Dryden.
      -- Help"less*ly, adv. -- Help"less*ness, n.
      [1913 Webster]

WordNet (r) 3.0 (2006):

helplessness
    n 1: powerlessness revealed by an inability to act; "in spite of
         their weakness the group remains active" [syn:
         helplessness, weakness, impuissance]
    2: the state of needing help from something
    3: a feeling of being unable to manage