| Name | Gender | Pronounced | Usage | Popularity |
|---|---|---|---|---|
| Ognen | - | Macedonian | ||
| Ognena | - | Macedonian | ||
| Olgica | - | Macedonian, Serbian | ||
| Oliver | AHL-ə-vər (English), AW-lee-ver (German), O-lee-ver (Finnish) | English, German, Swedish, Norwegian, Danish, Finnish, Estonian, Serbian, Croatian, Macedonian, Czech | ||
| Olivera | - | Serbian, Croatian, Macedonian |