trachtenberg, literally "a mountain of costumes" (in german), or "a mountain of thoughts" (in yiddish), is actually the former german name of a town in silesia now called by the polish name żmigród, where jews were a significant part of the population until the second world war and the holocaust. jews who bear this name are usually descendants of families who moved from trachtenburg, silesia, to another place in central or eastern europe (and then elsewhere, later on), and became known in their new communities by their former place of residence.