feebleness

from WordNet (r) 3.0 (2006)

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

from The Collaborative International Dictionary of English v.0.48

Feebleness \Fee"ble*ness\, n.
   The quality or condition of being feeble; debility;
   infirmity.
   [1913 Webster]

         That shakes for age and feebleness.      --Shak.
   [1913 Webster]