What do prefixes such as O, Mac, Mc, Fitz and Ni mean in Irish surnames?
Woulfe sets out the pattern plainly. Ó, written O' in English, means descendant of, originally grandson of, the man named after it. Mac means son of that man. Mc is simply a shortened written form of Mac and carries no separate meaning, and it is not a reliable marker of Scottish rather than Irish origin. Fitz came with the Normans, from the French for son, and sits in names such as FitzGerald and Fitzpatrick. In Irish language forms a daughter uses Ní with an Ó name and Nic with a Mac name, so Ní Cheallaigh is the daughter's form of Ó Ceallaigh, Kelly. These forms still appear on headstones and in Irish language documents, so they are worth recognising in the records.
Useful pages: The Irish surnames map · Trace your Irish roots · The 1926 Census guide · Coming home · Irish around the world · Plan your journey
Sources
- R. E. Matheson, Special Report on Surnames in Ireland; Patrick Woulfe, Irish Names and Surnames (1923)
More in Surnames and your Irish roots
- Where does the Irish Escapes surname information come from?
- What does the surname map actually show: where a name lives now or where it was rooted in 1890?
- How do I find my surname, its Irish form, meaning and heartland counties?
- My surname is not among the 795 mapped names. What should I do next?
- Does an Irish surname mean I can claim a family coat of arms?