An American with the same surname "Flack" contacted me and asked me if I had done a DNA test. He was looking for the area in Ireland that his ancestors came from and noted mine came from County Cavan. I agreed and the results showed that we both had "Affleck" connections to Ayreshire in Scotland via Northern Ireland within 10 generations! It has been suggested that "Flack" is probably an Irish shortening of "Affleck" - "from the place of the stones" eg "flagstones" etc "flagging", etc. My father believed it came from "flax" and was originally Dutch!