Jajac families are Croats and they are mostly from Sibenik. In the past century, relatively most of Croatian residents bearing this family name were born in Sibenik and Split.
Prevalence
About 70 people with faimily name Jajac live in Croatia today, in 40 households. There were 50 of them in the middle of the past century, and their number increased by 40 percent. They are only located in in 7 Croatian cities and threee other places, mostly in Sibenik (30), Split (15), Rijeka (15), Murter on the Island of Murter (<10), and in Zirje (<10).
Outside Croatia
Family name Jajac (including: Yayac , Jayac and Yayaz ) is present in 6 countries on three continents. The family name "Jajac " is used by small number of people in the United States. "Yayac " is used by small number of people in the United States.
In the sources analysed in the project Acta Croatica so far, the name is mentioned few times, the first time 1906 in source Yearbook and Directory of Literary Society of St. Jerome 1906.