The Collaborative International Dictionary of English v.0.48:

Disreputability \Dis*rep`u*ta*bil"i*ty\, n.
   The state of being disreputable. [R.]
   [1913 Webster]

WordNet (r) 3.0 (2006):

disreputability
    n 1: dishonorableness by virtue of lacking respectability or a
         good reputation [syn: unrespectability,
         disreputability, disreputableness] [ant:
         reputability, respectability]