Brennan

The name Brennan is a masculine Irish name derived from the Gaelic surname Ó Brannáin, meaning 'descendant of the sad one'. The name is derived from the Irish word 'brón', which means 'sorrow' or 'sadness'.

The name was originally a patronymic surname, indicating that the bearer was a descendant of someone with the personal name Brannán. The personal name Brannán itself is thought to have been derived from the Irish word 'bran', meaning 'raven' or 'crow'.

In Irish mythology, the raven or crow was often associated with battle and warfare, and it is believed that the name Brannán may have been given to someone who was known for their warlike or brave nature.

The name Brennan has been popular in Ireland for centuries and has since spread to other English-speaking countries, particularly the United States and Canada.