| Name | Gender | Pronounced | Usage | Popularity |
|---|---|---|---|---|
| OIGHRIG | - | Scottish | ||
| OIHANA | - | Basque | ||
| OILI | OY-lee | Finnish | ||
| OINONE | - | Greek Mythology | ||
| OKSANA | ahk-SAH-nah (Russian) | Ukrainian, Russian | ||
| OLÍVIA | - | Portuguese, Slovak, Hungarian | ||
| OLA (2) | AW-lah | Polish | ||
| OLALLA | o-LAH-yah | Spanish | ||
| OLAMIDE | - | Western African, Yoruba | ||
| OLAYINKA | - | Western African, Yoruba | ||
| OLEKSANDRA | - | Ukrainian | ||
| OLENA | - | Ukrainian | ||
| Olga | ['ɔlgə] | |||
| OLGA | OL-gah (Russian), AWL-gah (Polish, German) | Russian, Ukrainian, Polish, German, Swedish, Norwegian, Danish, Icelandic, Latvian, Hungarian, Itali | ||
| OLGICA | - | Macedonian, Serbian |