DuckCorp Dico

Found one definition

1.                 From English - German Ding/FreeDict dictionary ver. 1.9-fd1:
                   
   
   
                   
                     
   stoolie /stˈuːli/
    [Am.] Denunziant <masc>, Naderer <masc> [Ös.]  [pej.]
      Synonyms: squealer, snitch, stoolpigeon, shamus, fink
    see: squealers, snitches, stoolpigeons, stoolies, shamuses, finks