During my nine trips to Slovakia I on occasion come across a subject I have never known to exist. "Do Names" is one of those. Some may say that it is just an alias, but it is more. I learned of "Do Names" while doing some research at Plavnica City Hall. My translator said the registrar want to know if you know the person's "Do Name". That began a discussion on the subject.
The registrar said "Do Names" is an oral tradition in the area. Do in Slovak translates to "of". It had a specific use. When a family grew to a large number there was the problem of many members having the same given name. How could one tell one from another? That is where the "Do Name" came into use. First, branches of the family tree were identified. Those branches were given a "Do Name". In Hromos, my Mojher ancestral village, there were three "Do Names": Adama. Palody and Zid. A cousin explained the "Do Names", Adama root word is Adam, Palody root is Pal/Paul, and Zid translates to Jew. The Hromos Mayor told me the family lore is that a Mojher long ago saved a Jew from being killed and Zid became associated with that person's descendants. A cousin who is Roman Catholic had the nickname "Little Jew". He was very proud of the nickname. When he died his son carried on with the nickname. Say there was many Michal Mojhers in Hromos. When people was speaking about a particular Michal Mojher they would use his "Do Name". I am of the Adama line, so they would refer to me as Michal Adama. My Rindos family in Plavnica have five "Do Names". One translates to chicken**t.
For genealogists the "Do Names" are a double edged sword. It is great to have branches of a family identified. The bad, they are used in records. If you do not know your families "Do Name" they would seem to be just another surname. I have seen it in church records and land purchase documents. Having "Do Names" as an oral tradition only the locals know of them. And every once in awhile someone doing their genealogy.