| Name | Gender | Pronounced | Usage | Popularity |
|---|---|---|---|---|
| Onyeka | - | Western African, Igbo | ||
| Onyekachi | - | Western African, Igbo | ||
| Onyekachukwu | - | Western African, Igbo | ||
| Opeyemi | - | Western African, Yoruba | ||
| OphÉLie | o-fe-LEE | French | ||
| Ophir | - | Biblical | ||
| Ophrah | AWF-rə (English) | Biblical | ||
| Oriane | - | French | ||
| Orianne | - | French | ||
| Origenes | - | Ancient Greek | ||
| Oriol | - | Catalan | ||
| Orpah | AWR-pə (English) | Biblical | ||
| 'Orpah | - | Biblical Hebrew | ||
| Orpha | AWR-fə (English) | Biblical, English | ||
| Ortwin | AWRT-veen (German) | German, Ancient Germanic |