Source : Webster's Revised Unabridged Dictionary (1913)

Foulness \Foul"ness\, n. [AS. f?lnes.]
   The quality or condition of being foul.

Source : WordNet®

foulness
     n 1: a state characterized by foul or disgusting dirt and refuse
          [syn: {filth}, {filthiness}, {nastiness}]
     2: the attribute of having a strong offensive smell [syn: {malodorousness},
         {stinkiness}, {rankness}]