| Name | Gender | Pronounced | Usage | Popularity |
|---|---|---|---|---|
| OCEANUS | - | Greek Mythology (Latinized) | ||
| OCHIENG | - | Eastern African, Luo | ||
| OCTÁVIA | - | Portuguese | ||
| OCTÁVIO | - | Portuguese | ||
| OCTAVE | - | French | ||
| Octavia | [ɔk'teiviə] | |||
| OCTAVIA | ahk-TAYV-ee-ə (English) | English, Spanish, Ancient Roman | ||
| OCTAVIAN | ahk-TAYV-ee-ən (English) | History, Romanian | ||
| OCTAVIANUS | - | Ancient Roman | ||
| OCTAVIO | ok-TAH-vyo | Spanish | ||
| OCTAVIUS | ahk-TAYV-ee-əs (English) | Ancient Roman | ||
| ODA | O-dah (German) | German, Ancient Germanic | ||
| ODALIS | - | Spanish | ||
| ODALRIC | - | Ancient Germanic | ||
| ODALYS | - | Spanish |