The Etymology of the Surname Dudelsack/Dudelczak/Dudelzak

When I began researching, all I could find on my ancestral surname, Dudelsack, was the German bagpipe.

Later, once I realized 'Dudel' was a Yiddish diminutive for 'David,' I realized the surname was likely 'Dudelczak' or 'Dudelzak,' and patronymic in origin.

A different etymology is provided in Dictionary of Jewish Surnames From the Russian Empire, by Alexander Bieder, Avotaynu, 1993.

Dudel'zak (Pinsk, Lutsk, Ostrog, Odessa, Rovno) O: from 'nudlzak' [Southeastern Yiddish] needle packing. 

This would make it an occupational surname. Needle packing is probably related to the profession of tailor. The entry also provides some locations where the surname could be found.

It's worth noting that there are several surnames in the dictionary that are based on the Yiddish diminutive, 'Dudel.'