Source : Webster's Revised Unabridged Dictionary (1913)

Feebleness \Fee"ble*ness\, n.
   The quality or condition of being feeble; debility;
   infirmity.

         That shakes for age and feebleness.      --Shak.

Source : WordNet®

feebleness
     n 1: the state of being weak in health or body (especially from
          old age) [syn: {infirmity}, {frailty}, {debility}, {frailness}]
     2: the quality of lacking intensity or substance; "a shrill yet
        sweet tenuity of voice"- Nathaniel Hawthorne [syn: {tenuity}]