O'neil

O'neil Origin and Meaning

The name O'neil is a boy's name.

O'Neil is a masculine name with Irish origins, derived from the Gaelic surname Ó Néill, meaning "descendant of Niall." The name carries prestigious historical significance as it references one of Ireland's most powerful medieval dynasties, the O'Neill clan, who ruled as kings of Ulster. The name combines the prefix "Ó" (grandson or descendant of) with "Niall," an ancient Irish name possibly meaning "champion" or "passionate." As a first name, O'Neil emerged as part of the trend of using surnames as given names. The apostrophe gives it a distinctive appearance, and the name projects strength and Celtic heritage. While not extremely common as a first name, it appeals to parents seeking an Irish-connected name with historical depth.