Last Names That Start with O: A Comprehensive Guide

Are you looking for a unique and meaningful last name that begins with the letter O? Look no further! This comprehensive list features over 40 last names starting with O, along with their detailed origins and meanings. From classic and traditional to modern and uncommon, you'll find a wide variety of options to choose from. Whether you're searching for a surname with historical significance, a name that reflects your family heritage, or simply a name that sounds beautiful and elegant, this list has something for everyone.
1. **O'Brien:** Irish origin, meaning "descendant of Brian." Brian was a popular Irish king and warrior, making this surname a powerful and historically significant choice.
2. **O'Connell:** Irish origin, meaning "descendant of Connell." Connell was a common Gaelic name, making this surname a popular choice among Irish families.
3. **O'Donnell:** Irish origin, meaning "descendant of Donnell." Donnell is a Gaelic name meaning "lord of the world," giving this surname a sense of power and authority.
4. **O'Malley:** Irish origin, meaning "descendant of Maol-mhuire." This name is derived from the Gaelic words "maol" (bald) and "mhuire" (Mary), making it a unique and interesting surname.
5. **O'Neil:** Irish origin, meaning "descendant of Niall." Niall was a legendary king of Ireland, making this surname a symbol of Irish pride and heritage.
6. **O'Connor:** Irish origin, meaning "descendant of Conn." Conn was a legendary Irish king who is said to have been the ancestor of many Irish families.
7. **O'Reilly:** Irish origin, meaning "descendant of Raghallaigh." This name is derived from the Gaelic words "ragh" (brave) and "allaigh" (strong), making it a powerful and inspiring surname.
8. **O'Hara:** Irish origin, meaning "descendant of O'Hagan." This name is derived from the Gaelic word "oighre" (heir), making it a suitable choice for those who value lineage and heritage.
9. **Oliver:** Latin origin, meaning "olive tree." This name is known for its association with peace, hope, and prosperity, making it a popular choice for parents seeking a meaningful and positive name.
10. **Olson:** Scandinavian origin, meaning "son of Olaf." This name is a common surname in Scandinavian countries and reflects the strong family ties and traditions of the region.
11. **Owen:** Welsh origin, meaning "noble" or "well-born." This name is associated with strength, courage, and nobility, making it a suitable choice for those seeking a name with a strong and positive meaning.
12. **Odell:** English origin, meaning "from the hill." This name is a popular surname in England and reflects the historical significance of hills and mountains in the region.
13. **Ortiz:** Spanish origin, meaning "goldsmith." This name is associated with artistry, craftsmanship, and wealth, making it a suitable choice for those who appreciate beauty and creativity.
14. **Osborne:** English origin, meaning "from the bear's home." This name is a popular surname in England and reflects the historical presence of bears in the region.
15. **Osborn:** English origin, meaning "from the bear's home." This name is a variation of Osborne and shares the same meaning and origin.
16. **Otto:** German origin, meaning "wealthy" or "prosperous." This name is associated with success, fortune, and abundance, making it a suitable choice for those who value material wealth and prosperity.
17. **Overton:** English origin, meaning "over the town." This name is a common surname in England and reflects the historical location of villages and towns in the region.
18. **Odom:** English origin, meaning "from the hill." This name is a variation of Odell and shares the same meaning and origin.
19. **Ogilvie:** Scottish origin, meaning "descendant of Gille-Bride." This name is a popular surname in Scotland and reflects the historical significance of the region.
20. **O'Shaughnessy:** Irish origin, meaning "descendant of O'Seanachaidh." This name is derived from the Gaelic word "seanchaidh" (storyteller), making it a suitable choice for those who appreciate history, literature, and storytelling.
21. **O'Rourke:** Irish origin, meaning "descendant of Ruarc." This name is a popular surname in Ireland and reflects the historical significance of the region.
22. **O'Brien:** Irish origin, meaning "descendant of Brian." This name is a variation of O'Brien and shares the same meaning and origin.
23. **O'Leary:** Irish origin, meaning "descendant of Leary." This name is a popular surname in Ireland and reflects the historical significance of the region.
24. **O'Toole:** Irish origin, meaning "descendant of Tuathal." This name is a popular surname in Ireland and reflects the historical significance of the region.
25. **O'Connor:** Irish origin, meaning "descendant of Conn." This name is a variation of O'Connor and shares the same meaning and origin.
26. **O'Reilly:** Irish origin, meaning "descendant of Raghallaigh." This name is a variation of O'Reilly and shares the same meaning and origin.
27. **O'Hara:** Irish origin, meaning "descendant of O'Hagan." This name is a variation of O'Hara and shares the same meaning and origin.
28. **O'Neill:** Irish origin, meaning "descendant of Niall." This name is a variation of O'Neil and shares the same meaning and origin.
29. **O'Malley:** Irish origin, meaning "descendant of Maol-mhuire." This name is a variation of O'Malley and shares the same meaning and origin.
30. **O'Donnell:** Irish origin, meaning "descendant of Donnell." This name is a variation of O'Donnell and shares the same meaning and origin.
31. **O'Connell:** Irish origin, meaning "descendant of Connell." This name is a variation of O'Connell and shares the same meaning and origin.
32. **O'Brien:** Irish origin, meaning "descendant of Brian." This name is a variation of O'Brien and shares the same meaning and origin.
33. **O'Mara:** Irish origin, meaning "descendant of Meara." This name is a popular surname in Ireland and reflects the historical significance of the region.
34. **O'Meara:** Irish origin, meaning "descendant of Meara." This name is a variation of O'Mara and shares the same meaning and origin.
35. **O'Shea:** Irish origin, meaning "descendant of O'Suilleabhain." This name is derived from the Gaelic word "suilleabhain" (descendant of the blind one), making it a unique and interesting surname.
36. **O'Sullivan:** Irish origin, meaning "descendant of O'Suilleabhain." This name is a variation of O'Shea and shares the same meaning and origin.
37. **O'Driscoll:** Irish origin, meaning "descendant of Driscoll." This name is a popular surname in Ireland and reflects the historical significance of the region.
38. **O'Flynn:** Irish origin, meaning "descendant of Flann." This name is a popular surname in Ireland and reflects the historical significance of the region.
39. **O'Brien:** Irish origin, meaning "descendant of Brian." This name is a variation of O'Brien and shares the same meaning and origin.
40. **O'Connor:** Irish origin, meaning "descendant of Conn." This name is a variation of O'Connor and shares the same meaning and origin.
41. **O'Reilly:** Irish origin, meaning "descendant of Raghallaigh." This name is a variation of O'Reilly and shares the same meaning and origin.