It has been estimated that 80% of Irish surnames originally had an O' prefix.
O' in Irish surnames is from Ó (grandson,descendant) as in Ó Néill, grandson of Niall or Ó Briain from Brian, etc.
The Ó as in Ó Briain (O'Brien) comes from the older Irish word Ua (grandson, grandchild; descendant).
There are various beliefs into the origins of the Mullinsand Mullens surnames. The Irish belief is that it may be the Anglicisation of the Irish name O Maolain, from a diminutive of maol, meaning 'bald' or 'tonsured', which arose separately in a number of areas.
If "O" is before a last name, it is often an abbreviation for "Ó", which is a prefix in Irish surnames indicating "descendant of" or "grandson of." For example, O'Connor means "descendant of Connor." It signifies a connection to a particular ancestor in Irish heritage.
It is estimated that about 20% of Irish surnames have a Mac prefix. Mac means son; so Mac Carthaigh would mean 'son of Carthach'.
The surname Colton is spelled Coltún in Irish (Irish Names and Surnames, Woulfe).
Are you asking about Christian (first) names or Surnames? For surnames the prefix O' meaning grandson (of) also Mc/Mac meaning son (of) which is prevalant in the Highlands of Scotland as well. The two acounting for 25% of the top 100 most common surnames in Ireland.
In Ireland Justin is used even with Irish Gaelic surnames.
the "O" in Irish means son of as in O'Brien is son of Brien
It's either a typo or s/he works for Apple. It may mean that that a letter is missing; female Irish surnames begin with "ní" before the main name,meaning daughter of.
The clan of Farrell or O Farrell comes from Country Longford in The Irish Republic