| Nome | Sginificados | Sexo | Origem |
|---|---|---|---|
| Obelia | pillar of strength | Menina | Greek |
| Oceana | Ocean | Menina | Greek |
| Odele | Wealthy | Menina | Greek |
| Odessa | a long journey | Menina | Greek |
| Olivia | olive tree | Menina | Greek |
| Olympia | Mountain of the Gods | Menina | Greek |
| Ophelia | serpent | Menina | Greek |
| Oria | From the Orient | Menina | Greek |
| Oriana | Golden One | Menina | Greek |
| Orion | son of fire, the hunter | Menino | Greek |
| Otis | One Who Hears Well | Menino | Greek |
| Gaelic |
| Teutonic |
| Italian |
| Filipino |
| Vietnamese |