| Nombre | Origen | Evaluación | |
| Oidhche | Escocés | 0 | |
| Oifa | Celta | 0 | |
| Oifa | Celta | 0 | |
| Oighrig | Griego | 0 | |
| Oighrig | Griego | 0 | |
| Oihane | Español | 5 | |
| Oilbhe | Gaélico | 0 | |
| Oilell | Celta | 0 | |
| Oilell | Celta | 0 | |
| Oji | African | 0 | |
| Ojo | African | 0 | |
| Oke | Hawaiano | 5 | |
| Okelani | Hawaiano | 0 | |
| Okello | African | 0 | |
| Okes | Inglés | 0 | |
| Okhmhaka | Nativos americanos | 0 | |
| Oki | Japonés | 4.75 | |
| Okimma | African | 0 | |
| Oko | African | 3.5 | |
| Okoth | African | 0 | |