资料来源 : Webster's Revised Unabridged Dictionary (1913)

Frailness \Frail"ness\, n.
   Frailty.

资料来源 : WordNet®

frailness
     n : the state of being weak in health or body (especially from
         old age) [syn: {infirmity}, {frailty}, {debility}, {feebleness}]