desirability

from WordNet (r) 3.0 (2006)

desirability
    n 1: the quality of being worthy of desiring [syn:
         {desirability}, {desirableness}] [ant: {undesirability}]
    2: attractiveness to the opposite sex [syn: {sex appeal},
       {desirability}, {desirableness}, {oomph}]

from The Collaborative International Dictionary of English v.0.48

Desirability \De*sir`a*bil"i*ty\, n.
   The state or quality of being desirable; desirableness.
   [1913 Webster]