| # | ♂ | Name | Meaning | 
|---|---|---|---|
| 1 | ♂ | Oliver | Eleven | 
| 2 | ♂ | Omar | Life | 
| 3 | ♂ | Owen | Young warrior. Also can be a variant of Eugene: Well-born. | 
| 4 | ♂ | Onno | The generous | 
| 5 | ♂ | Oviel | |
| 6 | ♂ | Ole | What remains of the forefathers | 
| 7 | ♂ | Oshmar | |
| 8 | ♂ | Oussama | lion | 
| 9 | ♂ | Owemam | |
| 10 | ♂ | Orlando | brave, brave | 
| 11 | ♂ | Osvaldo | shapely, clean | 
| 12 | ♂ | Otoo | collecting sea shells in a basket | 
| 13 | ♀ | Olise | |
| 14 | ♂ | Otugoma | |
| 15 | ♀ | Odeke | |
| 16 | ♂ | Ollie | Diminutive of Oliver: Elf army. Can also be a variant of Olaf: Relic, ancestral heritage. | 
| 17 | ♂ | Orpaz | |
| 18 | ♂ | Oswaldo | shapely, clean | 
| 19 | ♂ | Oisin | Little | 
| 20 | ♂ | Onur | Honor | 
| 21 | ♂ | Osmo | |
| 22 | ♂ | Osama | A | 
| 23 | ♂ | Orges | |
| 24 | ♂ | Oskar | Spear of the gods | 
| 25 | ♂ | Oiva | Superior | 
| 26 | ♂ | Ozzy | Diminutive of Oswald: Divine power. | 
| 27 | ♂ | Onisimos | |
| 28 | ♂ | Oren | Jerusalem Pine | 
| 29 | ♂ | Okke | variant of Germanic | 
| 30 | ♂ | Omawnakw | Cloud feather (Hopi). | 
| 31 | ♀ | Onyx | a semi-precious stone | 
| 32 | ♂ | Olympio | From Mount Olympus | 
| 33 | ♂ | Othman | Wealthy. | 
| 34 | ♂ | Odd Asbjørn | |
| 35 | ♀ | Origanal | |
| 36 | ♂ | Orrin | The name of an English river. | 
| 37 | ♀ | Owen Sparkes | |
| 38 | ♀ | Ona | One. Also a variant of Una: Lamb; together. | 
| 39 | ♀ | Olivia | olive tree | 
| 40 | ♂ | Otto | Wealth | 
| 41 | ♂ | Osman | Godly protection, a combination of the Old Norse words "ass" and "mundr." | 
| 42 | ♀ | Oraliz | |
| 43 | ♂ | Onterio | |
| 44 | ♂ | Oriol | 
| # | ♂ | Name | Meaning | 
|---|---|---|---|
| 1 | ♀ | Olivia | olive tree | 
| 2 | ♀ | Odunayo | |
| 3 | ♀ | Olga | holy | 
| 4 | ♀ | Ouiam | Harmony, reconciliation | 
| 5 | ♀ | Odina | from the road | 
| 6 | ♀ | Ogochukwu | |
| 7 | ♀ | Oksana | Praise Be To God | 
| 8 | ♀ | Omulie | |
| 9 | ♂ | Oluwatobi | God is great | 
| 10 | ♀ | Ornela | |
| 11 | ♀ | Oyuka | |
| 12 | ♀ | Otilija | |
| 13 | ♀ | Oshaira | |
| 14 | ♀ | Olinda | olive tree | 
| 15 | ♀ | Oda | Elfin spear. | 
| 16 | ♀ | Ondinea | |
| 17 | ♂ | Opeyemi | Worship God | 
| 18 | ♀ | Olive | olive branch, peace | 
| 19 | ♀ | Osira | |
| 20 | ♀ | Ouissal | Connected in love | 
| 21 | ♀ | Origanal | |
| 22 | ♀ | Ouahiba | Principal, auxiliary regulatory | 
| 23 | ♀ | Olta | |
| 24 | ♀ | Oriane | abundant | 
| 25 | ♂ | Orion | Dweller On The Mountain | 
| 26 | ♀ | Olitjana | |
| 27 | ♀ | Oshin | |
| 28 | ♀ | Oixie | |
| 29 | ♀ | Ogbonna Emmanuella | |
| 30 | ♀ | Ondra | |
| 31 | ♀ | Olinka | |
| 32 | ♀ | Oulduz | |
| 33 | ♀ | Octavia | Born eighth. | 
| 34 | ♂ | Orges | |
| 35 | ♂ | Oof | |
| 36 | ♀ | Olympia | Mountain Of The Gods | 
| 37 | ♀ | Oumayma | |
| 38 | ♀ | Orllena | |
| 39 | ♀ | Oya | Wind Warrior Goddess | 
| 40 | ♀ | Odara | Unknown | 
| 41 | ♀ | Oceane | Ocean | 
| 42 | ♀ | Oluwayemisi | Honored by God | 
| 43 | ♀ | Ofelia | Helper | 
| 44 | ♀ | Oddette | |
| 45 | ♀ | Ocèana | Marine | 
| 46 | ♀ | Okena | Water Chief | 
| 47 | ♂ | Otoo | collecting sea shells in a basket | 
| 48 | ♀ | Oriana | Golden. | 
| 49 | ♀ | Oluwafunmilayo | With joy the gift of God | 
| 50 | ♀ | Orchid |