| # | NAME | MEANING | RELIGION |
| 1 | Oachim | God will establish | Christian |
| 2 | Oakley | Oak-tree field | Christian |
| 3 | Obadiah | Servant of god | Christian |
| 4 | Obed | A short form of obadiah | Christian |
| 5 | Oberon | elfruler | Christian |
| 6 | Octavian | Eighth | Christian |
| 7 | Oded | Strong omar - first son, disciple | Christian |
| 8 | Odell | woad(aplantyieldingbluedye) | Christian |
| 9 | Odran | littles allowone | Christian |
| 10 | Ofer | gold | Christian |
| 11 | Ogden | Oak valley. | Christian |
| 12 | Olaf | The remaining of the ancestors | Christian |
| 13 | Ole | Ancestor | Christian |
| 14 | Oli | elfarmy | Christian |
| 15 | Olin | Holly | Christian |
| 16 | Ollie | A familiar form of oliver | Christian |
| 17 | Olliver | Elf army | Christian |
| 18 | Olsen | Son of ole | Christian |
| 19 | Olson | Son of ole | Christian |
| 20 | Omar | Long life, first son, most high, the prophet's follower | Christian |
| 21 | Omarr | Long life , first son , most high , the prophet's follower | Christian |
| 22 | Ommar | Long life , first son , most high , the prophet's follower | Christian |
| 23 | On | vigor | Christian |
| 24 | Onam | vigorous, strong | Christian |
| 25 | Ophir | Honest | Christian |
| 26 | Oran | Pale one; pine ornice - cedar tree | Christian |
| 27 | Orian | privilegedbirth | Christian |
| 28 | Orlondo | Famous country | Christian |
| 29 | Ormerod | clearing, | Christian |
| 30 | Ormond | Bear mountain; spear protector | Christian |
| 31 | Orran | The name of an english river | Christian |
| 32 | Orrell | ore | Christian |
| 33 | Orren | From the pine tree / a pale-skinned man | Christian |
| 34 | Orrick | Old oak tree | Christian |
| 35 | Orrin | River | Christian |
| 36 | Orson | bear, | Christian |
| 37 | Orton | Shore town | Christian |
| 38 | Orval | A form of orville | Christian |
| 39 | Orville | goldencity | Christian |
| 40 | Orvin | Spear friend | Christian |
| 41 | Osaze | Favoured by god | Christian |
| 42 | Osbaldo | Uncertain | Christian |
| 43 | Osbert | Divine; bright | Christian |
| 44 | Osborn | Warrior of god | Christian |
| 45 | Osborne | Soldier of god | Christian |
| 46 | Osbourne | divine-bear | Christian |
| 47 | Oscar | god-spear | Christian |
| 48 | Osman | divine protection | Christian |
| 49 | Osmar | Divine; wonderful | Christian |
| 50 | Osmond | Divine protector. | Christian |
| 51 | Osric | Divine ruler | Christian |
| 52 | Oswald | God's power; god's crest | Christian |
| 53 | Oswaldo | Uncertain | Christian |
| 54 | Oswin | Divine friend. | Christian |
| 55 | Othello | young bull | Christian |
| 56 | Othniel | lion of God | Christian |
| 57 | Owen | bornofyew | Christian |
| 58 | Owenn | A well- born man | Christian |
| 59 | Oxley | Ox meadow | Christian |
| 60 | Oxton | Ox town | Christian |
| 61 | Oz | Strength | Christian |
| 62 | Ozzie | A familiar form of osborn | Christian |
| 63 | Ozzy | A familiar form of osborn | Christian |
