| Olgy | A holy and noble ancestor |
| Olia | Highest; loftiest; upmost |
| Olivine | A pretty light green stone |
| Olle | The remaining of the ancestors |
| Ollive | Olive branch; symbol of peace |
| Ollivia | A peaceful olive branch |
| Olufunke | God took care of |
| Olva | An olive tree or peaceful one. |
| Ombeline | A name meaning little shadow. |
| Omla | A name meaning golden or bright. |
| Omnia | Its A Latin Plural Of All |
| Omrana | Omrana means 'blessed' or 'fortunate' in Arabic, often used as a feminine given name. |
| Ondine | A spirit of the water element. |
| Ong Leng Huoy | Dragon's flame or fiery dragon, a name symbolizing strength, power, and fierce determination. |
| Onyeka | God is the greatest |
| Onyekachi | God is the greatest |
| Ooghavathi | One who possesses great waves. |
| Oordhvadevi | A goddess of the high heavens. |
| Oormilaa | A person with calm, gentle waves. |
| Ooshmaa | Represents warmth or heat. |
| Ooti | Protection; kindness |
| Orail | A name meaning golden or light. |
| Oranous | One Of The 9 Solar Plannets |
| Orchid | A beautiful, exotic flower type. |
| Oreen | From the pine tree; a pale-skinned man |
| Oriane | Meaning sunrise or golden dawn. |
| Orianne | A variation meaning golden light. |
| Orkideh | The Persian word for an orchid. |
| Orlah | Golden princess |
| Orra | Light or illumination of spirit. |
| Orub | Devoted; loving; full of love |
| Orush | A name meaning light or brilliance. |
| Orya | A name meaning light or radiance. |
| Ossia | A musical term meaning alternatively. |
| Osul | Figuratively principles; essentials |
| Othelia | One who is wealthy or prosperous. |
| Ourra tul ain | Delight Of Eye; Darling |
| Oadirah | A Powerful Woman |
| Oafiqa | A name meaning wise and learned. |
| Oalisa | A noble and kindhearted person. |