DuckCorp Dico

Found one definition

1.                 From German - English Ding/FreeDict dictionary ver. 1.9-fd1:
                   
   
   
                   
                     
   Flappe /flˈapə/ <fem, n, sg>
    [Norddt.]  [Mittelwestdt.]  [ugs.] pout <n>, trap <n>, gob <n> [Br.]  [coll.]
      Synonyms: Schmollmund, Flunsch, Schnute, Schnütchen, Schnoferl