incredibility

from WordNet (r) 3.0 (2006)

incredibility
    n 1: the quality of being incredible [syn: {incredibility},
         {incredibleness}] [ant: {believability}, {credibility},
         {credibleness}]

from The Collaborative International Dictionary of English v.0.48

Incredibility \In*cred`i*bil"i*ty\, n. [L. incredibilitas: cf.
   F. incr['e]dibilit['e].]
   [1913 Webster]
   1. The quality or state of being incredible; incredibleness.
      --Dryden.
      [1913 Webster]

   2. That which is incredible. --Johnson.
      [1913 Webster]