fustĭtŭdĭnus — Lewis & Short
fustĭtŭdĭnus, a, um, adj.fustistundo,
I cudgel-banging, a word comically formed to indicate the place where slaves were beaten:
apud fustitudinas ferricrepinas insulas, i. e. ergastula,Plaut. As. 1, 1, 21.