Probably not derogatory, possibly self-referential. Most likely from sometime between the turn of the century and the early sixties. I have only found one reference to it, but I believe it is most likely from the fact that in the first half of the twentieth century, for a period almost fifty percent of the Bronx was Jewish, thus they were seemingly like the native population of the Bronx.
Usage: Contributions needed!
Similar: Contributions needed!