A word that pops up in Elmer Rice’s Street Scene, both the stage play (1929) and the screenplay (1931):
Shirley (played by Anna Konstant [or Ann Kostant]) pronounces it BATE-sim-uh, or something like that, which suggests that it might also be transcribed as behtzimmer.
The closed captioning on the TCM streaming version of the film doesn’t even try to transcribe the word.
Modulo some search hits on the name of a porn performer, the only thing that turns up is some semi-speculation in a comment thread, suggesting the word has a connection to bathroom. But I’m not convinced, because that would suggest a pronunciation like BAHT-sim-uh.
German bettzimmer is bedroom, perhaps more promising.
It could always be something that Rice heard wrong, or just made up.