From German - English Ding/FreeDict dictionary ver. 1.9-fd1:
Gosche /ɡˈɔʃə/ <fem, n, sg>
[Bayr.] [Ös.] trap <n>, chops <n>, jaws <n>, maw <n>, gob <n> [Br.] , mush <n> [Br.] , cake-hole <n> [Br.] , pie hole <n> [Am.] , bazoo <n> [Am.] , yap <n> [Am.] [coll.]
Note: mouth
"Halt die Goschen!" - Keep your trap shut!, Shut up your piehole!
Synonyms: Maul, Schnabel, Schnauze, Futterluke, Klappe, Fresse, Sabbel, Pappe, Schnorre, Latz