| Name | Gender | Pronounced | Usage | Popularity |
|---|---|---|---|---|
| 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 | ||
| Orpha | AWR-fə (English) | Biblical, English | ||
| Ortwin | AWRT-veen (German) | German, Ancient Germanic | ||
| Osama | - | Arabic | ||
| Osanne | - | French (Rare) | ||
| Oscar | AHS-kər (English) | English, Irish, Portuguese (Brazilian), Italian, Swedish, Norwegian, Danish, Dutch, French, Irish My | ||
| Osee | - | Biblical Latin, Biblical Greek | ||
| Oshea | - | Biblical |