Zwerdling (Przemyśl, Kamionka, Lwów, Stryj, Dolina, Borszczów, Czortków, Rohatyn, Brzeżany, Trembowla, Skałat, common in Tarnopol; Zbaraż, Przemyślany, common in Złoczów; Brody)
A: from ‘Schwertklinge’ [German] sword blade(?) {Zwerdiig, Zwerling, Zwertling, Zwerlinger}.
From A Dictionary Of Jewish Surnames From Galicia by Alexander Beider
The Zwerdling family name appears to have originated in the region of Galicia in Austria-Hungary around 1788, which is when the Austrian emperor decreed every citizen must use a German-style hereditary surname.