| Ogaleesha | Wears a red shirt (Sioux) |
| Ogin | A name meaning the rising sun. |
| Oha | Meditation, true knowledge |
| Ohanko | Meaning a gift from the gods. |
| Ohanzee | A name meaning a dark shadow. |
| Ohas | Meaning a person of high rank. |
| Ohcumgache | Little wolf (Cheyenne) |
| Ohitekah | A Sioux name meaning to be brave. |
| Ojal | A name meaning vision or sight. |
| Ojas | Body strength; Brilliance, shine, glow; Lustre; Vitality |
| Ojaswini | One who is very luminous |
| Ojayit | One who is very glorious |
| Okhmhaka | Little wolf (Cheyenne) |
| Olathe | A name meaning beautiful place. |
| Olichudar | Brilliant; Brilliant; also OliSudar |
| Olikodi | A unique, melodic name. |
| Olimani | Meaning a heavenly spirit. |
| Olivia | Feminine form of Oliver; of the olive tree; one who is peaceful; Olive; Peace - Of The Olive Tree; 'Twelfth Night', also called 'What You Will' A rich countess.; Variant of Olive: Olive: symbol of peace. |
| Oliyarasi | A name meaning queen of olives. |
| Olwyn | Daughter of a giant |
| Oma | Cedar tree; The color of olive; Commanding; Commander; Life giver; Named for Bona Dea. |
| Omala | Earth or the goddess of earth |
| Omana | A gentle and loving woman |
| Omanand | The joy of the divine sound. |
| Omar | Elevated; An era; A flourishing man; one who is well-spoken; First born son; He that speaks; bitter; Life. Long living.; Long-lived.; Speaker. 12th century Persian poet and astronomer and mathematician Omar Khayyam. Caliph Omar II made Islam an imperial p |
| Omawnakw | Cloud feather (Hopi) |
| Ominotago | Beautiful voice (Chippewa) |
| Omja | Born of cosmic unity |
| Omkar | Religious word OM; The sound of the sacred syllable; Sound of Om, divine, sound |
| Omkarnath | Lord Shiva; Lord of Omkaar, shiva; Shiva |
| Omprakash | Light of God; Light Of Om; Sacred light |
| Omran | Solid structure |
| Omswaroop | Manifestation of divinity |
| Omvati | Sacred, Having the power of Om |
| Onawa | A name meaning wide awake person. |
| Onella | Light; Torch Light |
| Oni | Born On Holy Ground; Shelter; Wanted. |
| Onida | The one searched for |
| Onilee | Onilee is a variant of O'Neil, meaning 'champion' or 'noble' in Irish Gaelic. |
| Oojam | A name meaning joy and spirit. |