Starting with letter O
| # | Name | Origin | Meaning | Gender | |
|---|---|---|---|---|---|
| 301 | Os | English | Divine. | M | |
| 302 | Os | Norse | Divine. | M | |
| 303 | Osahar | Egyptian | God hears me. | M | |
| 304 | Osaze | Egyptian | Loved by God. | M | |
| 305 | Osbart | English | Divinely brilliant. | M | |
| 306 | Osbeorht | English | Divinely brilliant. | M | |
| 307 | Osbert | English | Divinely brilliant. | M | |
| 308 | Osborn | English | Divine warrior. | M | |
| 309 | Osborn | Norse | Divine bear. | M | |
| 310 | Osborn | Teutonic | Divine bear. | M | |
| 311 | Osborne | English | Variant of Osborn: Divine warrior. | M | |
| 312 | Osborne | Norse | Variant of Osborn: Divine bear. | M | |
| 313 | Osboume | Teutonic | Divine bear. | M | |
| 314 | Osbourne | English | Divine warrior. | M | |
| 315 | Osburn | English | Divine warrior. | M | |
| 316 | Osburt | English | Divinely brilliant. | M | |
| 317 | Oscar | Celtic | Jumping fighter. | M | |
| 318 | Oscar | English | Divine spear; God's spear. Famous Bearer: poet Oscar Wilde (1854-1900), who was put on trial and imprisoned for homosexuality. | M | |
| 319 | Oscar | Norse | Divine spear. | M | |
| 320 | Osckar | Celtic | Jumping fighter. | M | |