Source : Webster's Revised Unabridged Dictionary (1913)

Murkiness \Murk"i*ness\, n.
   The state of being murky.

Source : WordNet®

murkiness
     n 1: an atmosphere in which visibility is reduced because of a
          cloud of some substance [syn: {fog}, {fogginess}, {murk}]
     2: the quality of being cloudy [syn: {cloudiness}, {muddiness}]