O'Brennan Surname Meaning & Coat of Arms

O'Brennan is how some branches of the Brennan family came to write their name. Name scholars give the meaning as “Descendant of Braonán”.

• Other spellings include Brannan, Brannon and Ó Braonáin.
• Spellings drifted because names were written down by ear in parish books, tax rolls and passenger lists.
• The O' in front of the name is a particle that was often added to Brennan on registers.

Heraldry and the O'Brennan name

Looking for a O'Brennan coat of arms? Arms were granted to families, not to surnames, and our research shows which heraldic tradition fits yours. Want more than a summary? See the O'Brennan family name pack.