The name is Jewish and comes originally from Latvia (Lutzin) - and was styled as Zhmud, Zmood, which derives from the original "Zhmudze" - meaning "lowlander", as I understand it. The Zhmud family migrated with fellow members of the Latvian and Lithuanian Jewish communities to the Jewish agricultural settlements in the Ukraine and, from there, most left before WWII to the West. Almost all of those who remained perished in the war, with some still bearing the name in the Ukraine. Most migrated to Australia and remain Jewish to this day.