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Surname O'Neil - Meaning and Origin

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O'Neil: What does the surname O'Neil mean?

The last name O'Neil is an Irish-originated surname derived from the Gaelic name Ó Néill (grandson of Neil or Niall). O'Neil is one of the most common names of Irish ancestry both in Ireland and in the United States.

The origin of O'Neil dates back to the 5th century when the legendary Niall of the Nine Hostages established the Uí Néill dynasty. The dynasty was responsible for defending the northern part of Ireland against invaders and rampant clans. It is from this dynasty the O'Neils descended.

Notably, the O'Neils of Clannaboy originated from a branch of the wider O'Neil clan. This was a federation of Irish clans that were loyal to the king of Ulster. Many also have descended from the O'Neils of Tyrone, who were powerful lords in eastern Ulster and descended from the kings of Ulster.

O'Neil is a proud family name throughout Ireland and beyond. It represents the strength, spirit, and resilience of the Irish people. Those with this proud name can be proud to be part of such a distinguished clan.

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O'Neil: Where does the name O'Neil come from?

The O’Neil surname is found in many countries around the world, although the highest concentrations are in Ireland and, to a lesser extent, the United States. According to the US Census Bureau, the last name O'Neil is most common in the US states of Massachusetts, Rhode Island, and New Hampshire - and these states also have the highest population of people with Irish ancestry. In Ireland, O'Neil is the 10th most common surname. It is widely distributed across the entire island of Ireland and is particularly common in the provinces of Ulster and Connacht. In the United Kingdom, the O'Neil surname is most common in England and Scotland.

Overall, O'Neil is a surname with a long history that spans various countries and cultures. It has been in use since the 12th century in Ireland and took on various forms as more people emigrated to Britain and elsewhere. Today, it is still quite common in many areas where Irish ancestry is strong. Those bearing the name O'Neil are likely to find many people they can bond with over their shared name, wherever it be on the world map.

Variations of the surname O'Neil

The O’Neil family has a long history and a variety of different variants, spellings, and surnames. The most common surname derived from O’Neil, and the most ancient, is Ó Nualláin, which is Gaelic in language and origin. In English variants, O’Neal is the most popular spelling. O’Neill can be used in both Irish and Scottish contexts. It can also be spelt with a single 'l', as O'Neil, or O'Neale. O’Niel is another common spelling, while O’Nealon is another Irish variant.

Other spellings include Neale, Neal, Nihill, Nihalle, Nihell, Nihill, Neill,Neill, mac Neil, and McNeal. For Scottish families, occasionally surnames like MacNeil, MacNeal, McNeil, or McNeal can be used.

In less common cases, the surname may be derived from from other Gaelic roots. For example, it may be derived from O'hAnluain, which originated in Ireland as an Anglicized spelling. It can also be derived from a Norman surname, Nele, or from the Gaelic word “suil” meaning “eye," as O'Neill means “descendant of Niall,” a given name commonly meaning “champion.”

Many of these different surnames of O’Neil origin are found in the United Kingdom, the United States, Ireland, Canada, Australia, and other parts of the world.

Famous people with the name O'Neil

  • Donald O'Neil: American actor
  • Mark O'Neil: Australian diver
  • Nigel O'Neil: British actor
  • Ed O'Neil: American actor
  • James O'Neil: Irish poet
  • Donal O'Neil: Irish rugby league footballer
  • Matthew O'Neil: Canadian actor
  • Troy O'Neil: American baseball player
  • John O'Neil: American security consultant
  • Charlotte O'Neill: British television presenter
  • Hugh O'Neil: American former Army general
  • Robert M. O'Neil: American constitutional law scholar
  • Jack O'Neill: American surfer
  • Chester O'Neil: Australian rules footballer
  • Ryan O'Neil: American former baseball player
  • Ethel O'Neill: American stage and film actress
  • Stephen O'Neil: Canadian television presenter
  • Sean O'Neil: American former football player
  • Mason O'Neill: Canadian actor and artist
  • Chris O'Neil: Australian rules footballer

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