Source : Webster's Revised Unabridged Dictionary (1913)

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.

            How shall I then your helpless fame defend? --Pope.

   2. Beyond help; irremediable.

            Some helpless disagreement or dislike, either of
            mind or body.                         --Milton.

   3. Bringing no help; unaiding. [Obs.]

            Yet since the gods have been Helpless foreseers of
            my plagues.                           --Chapman.

   4. Unsupplied; destitute; -- with of. [R.]

            Helpless of all that human wants require. --Dryden.
      -- {Help"less*ly}, adv. -- {Help"less*ness}, n.

Source : WordNet®

helpless
     adj 1: lacking in or deprived of strength or power; "lying ill and
            helpless"; "helpless with laughter" [syn: {incapacitated}]
     2: unable to function; without help [syn: {lost}]
     3: unable to manage independently; "as helpless as a baby"