DuckCorp Dico

Found one definition

1.                 From WordNet (r) 3.0 (2006):
                   
   
   
                   
                     
   sizz
       v 1: express or utter with a hiss [syn: hiss, sizz, siss,
            sibilate]
       2: make a sharp hissing sound, as if to show disapproval [syn:
          hiss, siss, sizz, sibilate]