Last Names Starting with O: A Comprehensive Guide

Looking for a unique and meaningful last name that starts with the letter O? This comprehensive list provides over 40 options, each accompanied by its detailed origin and meaning. Whether you're searching for a name with a strong historical connection or a modern and stylish feel, this guide has something for everyone. Explore the rich tapestry of O-starting last names and discover the perfect fit for your family.
1. **O'Brien:** Irish, meaning "descendant of Brian". Brian is a popular Irish name meaning "strong" or "noble".
2. **O'Connell:** Irish, meaning "descendant of Connell". Connell is an Irish name meaning "descendant of Conn", a legendary king.
3. **O'Connor:** Irish, meaning "descendant of Conor". Conor is an Irish name meaning "lover of hounds".
4. **O'Donnell:** Irish, meaning "descendant of Donal". Donal is an Irish name meaning "world ruler".
5. **O'Neill:** Irish, meaning "descendant of Niall". Niall is an Irish name meaning "champion".
6. **O'Hara:** Irish, meaning "descendant of Ó hAodha". Ó hAodha is an Irish name meaning "descendant of Aodh", which means "fire".
7. **O'Reilly:** Irish, meaning "descendant of Raghallaigh". Raghallaigh is an Irish name meaning "fiery king".
8. **O'Rourke:** Irish, meaning "descendant of Ruairc". Ruairc is an Irish name meaning "red king".
9. **Oliver:** English, meaning "olive tree". Olive trees symbolize peace, fertility, and victory.
10. **Owen:** Welsh, meaning "noble" or "well-born". It is also a common name in Irish and English.
11. **Otto:** German, meaning "wealthy" or "prosperous". It is also a common name in Scandinavian countries.
12. **Oscar:** Scandinavian, meaning "god's spear". It is a popular name in many countries, including Ireland, England, and Germany.
13. **Ortega:** Spanish, meaning "bear". It is a common surname in Spain and Latin America.
14. **Olsen:** Norwegian, meaning "son of Ole". Ole is a common Scandinavian name meaning "ruler".
15. **O'Malley:** Irish, meaning "descendant of Maol-mhuadhaigh". Maol-mhuadhaigh is an Irish name meaning "bald ruler".
16. **Omar:** Arabic, meaning "flourishing" or "prosperous". It is a popular name in the Middle East and North Africa.
17. **Orlando:** Italian, meaning "famous land". It is a popular name in many countries, including Italy, Spain, and France.
18. **Ortiz:** Spanish, meaning "golden" or "goldsmith". It is a common surname in Spain and Latin America.
19. **Osborne:** English, meaning "divine horse". It is a common surname in England and the United States.
20. **O'Shea:** Irish, meaning "descendant of Seán". Seán is an Irish name meaning "God is gracious".
21. **Otis:** Greek, meaning "ear". It is a common surname in the United States.
22. **Oakley:** English, meaning "oak clearing". Oak trees symbolize strength, wisdom, and longevity.
23. **Odom:** English, meaning "dweller at the hill".
24. **Odell:** English, meaning "dweller at the hill".
25. **O'Brien:** Irish, meaning "descendant of Brian", a popular Irish name meaning "strong" or "noble".
26. **O'Connor:** Irish, meaning "descendant of Conor", an Irish name meaning "lover of hounds".
27. **O'Donnell:** Irish, meaning "descendant of Donal", an Irish name meaning "world ruler".
28. **O'Neill:** Irish, meaning "descendant of Niall", an Irish name meaning "champion".
29. **O'Hara:** Irish, meaning "descendant of Ó hAodha", an Irish name meaning "descendant of Aodh", which means "fire".
30. **O'Reilly:** Irish, meaning "descendant of Raghallaigh", an Irish name meaning "fiery king".
31. **O'Rourke:** Irish, meaning "descendant of Ruairc", an Irish name meaning "red king".
32. **O'Malley:** Irish, meaning "descendant of Maol-mhuadhaigh", an Irish name meaning "bald ruler".
33. **O'Shea:** Irish, meaning "descendant of Seán", an Irish name meaning "God is gracious".
34. **Oliver:** English, meaning "olive tree", a symbol of peace, fertility, and victory.
35. **Owen:** Welsh, meaning "noble" or "well-born", also common in Irish and English.
36. **Otto:** German, meaning "wealthy" or "prosperous", also common in Scandinavian countries.
37. **Oscar:** Scandinavian, meaning "god's spear", popular in Ireland, England, and Germany.
38. **Ortega:** Spanish, meaning "bear", common in Spain and Latin America.
39. **Olsen:** Norwegian, meaning "son of Ole", a common Scandinavian name meaning "ruler".
40. **Omar:** Arabic, meaning "flourishing" or "prosperous", popular in the Middle East and North Africa.
41. **Orlando:** Italian, meaning "famous land", popular in Italy, Spain, and France.
42. **Ortiz:** Spanish, meaning "golden" or "goldsmith", common in Spain and Latin America.
43. **Osborne:** English, meaning "divine horse", common in England and the United States.
44. **Otis:** Greek, meaning "ear", common in the United States.
45. **Oakley:** English, meaning "oak clearing", oak trees symbolize strength, wisdom, and longevity.
46. **Odom:** English, meaning "dweller at the hill".
47. **Odell:** English, meaning "dweller at the hill".