| Name | Meaning | Details |
|---|---|---|
| Oakley | From The Oak Tree Field | View Details |
| Oisin | Little Deer | View Details |
| Oleander | Evergreen Tree | View Details |
| Olive | Olive Or From The Olive Tree | View Details |
| Ondelette | Little Wave | View Details |
| Ordell | Little Knife | View Details |
| Orinda | Pine Trees | View Details |
| Ornella | Flowering Ash Tree | View Details |
| Owen | The Yew Tree Or Youth | View Details |
| Paget | Little Page | View Details |
| Park | Cypress Tree | View Details |
| Peri | Dweller By The Pear-tree | View Details |
| Perlita | Little Pearl | View Details |
| Perry | Dweller By The Pear Tree | View Details |
| Polina | Little Stone | View Details |