Source : Webster's Revised Unabridged Dictionary (1913)

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

Source : WordNet®

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