| Name | Gender | Pronounced | Usage | Popularity |
|---|---|---|---|---|
| Oriane | - | French | ||
| Orianne | - | French | ||
| Origenes | - | Ancient Greek | ||
| Orinda | - | English (Rare) | ||
| Ormond | AWR-mənd | English (Rare) | ||
| Ormonde | - | English (Rare) | ||
| Orpha | AWR-fə (English) | Biblical, English | ||
| Orrell | - | English (Rare) | ||
| Orson | AWR-sən | English | ||
| Ortwin | AWRT-veen (German) | German, Ancient Germanic | ||
| Orval | AWR-vəl | English | ||
| Orville | AWR-vil | English | ||
| Osanne | - | French (Rare) | ||
| Osbert | AHZ-bərt | English (Rare) | ||
| Osborn | AHZ-born | English |