Meaning and name origin
O'Brien \o-brien, ob-rien\ as a boy's name is of Celtic, Irish and Gaelic origin, and the meaning of O'Brien is "high, noble". O'Brien is a variant of Brian (Celtic, Irish, Gaelic): could also mean "strength".
O'Brien is not a popular first name for males and an equally uncommon surname or last name for all people (2000 U.S. Census).
Displayed below is a comparison of the popularity of the boy name O'Brien and its source form. The only popular variation form ranked in the Top 1000/100 is Brian (#168). (2014 statistics).