| Octavien | Derived from Latin 'octavus,' meaning eighth, possibly referring to birth order or eighth child. |
| Octavo | The eighth born in a family. |
| Odelya | I will honour God |
| Odern | Modern means being in accordance with the present or the most recent time period. |
| Odilio | One who is wealthy or rich. |
| Odis | Odys means 'traveler' or 'wanderer' in Greek, derived from the word 'odysseia' meaning journey. |
| Odiya | I will honour God |
| Odubel | O'Dubel is an Irish surname meaning 'descendant of Dubhghaill,' meaning 'dark stranger' or 'dark foreigner'. |
| Ofemija | A name meaning to be loved. |
| Ofure | It means peace or calmness. |
| Og | A cake bread baked in ashes |
| Ogechi | The greatest of Gods times |
| Ogechukwukama | The greatest of Gods times |
| Ogen | It means a gift from heaven. |
| Ogow | It means a source of wisdom. |
| Ohab | It means a beloved person. |
| Ohaba | It means a joyful greeting. |
| Ohada | It means a noble assembly. |
| Ohage | Ohage is a Japanese surname meaning 'great rice field' or 'large paddy field'. |
| Ohara | It means a small meadow. |
| Ohawna | Gods gracious gift |
| Oheo | It means a beautiful place. |
| Ohitika | Ohitika is a Maori name meaning 'to be in a state of being free from care or worry'. |
| Ohndrea | It means a brave warrior. |
| Ohndreea | It means a strong spirit. |
| Ohndria | A variant of Andrea meaning brave. |
| Oiley | Derived from oil, meaning smooth. |
| Oili | A Finnish name meaning holy one. |
| Oisyn | A name meaning a small deer fawn. |
| Oka | A name meaning one from the river. |
| Okendra | A name meaning a powerful ruler. |
| Okey | Derived from the Choctaw Native American word 'okeh,' meaning 'it is so' or 'agreement.' |
| Oksanna | A name meaning praise to God. |
| Oktovia | A name meaning the eighth born. |
| Olajuwan | Olajuwan means 'God is my strength' or 'God is my protector' in Yoruba language. |
| Olan | Derived from Gaelic, 'Olan' means 'descendant of the champion' or 'strong and powerful'. |
| Olavi | Ancestors descendant or heir |
| Olavo | A noble and ancestral legacy |
| Olbracht | A bright and noble heritage |
| Oldrich | A ruler of noble heritage |