| Name | Meaning | Gender | Origin |
|---|
| Old Deuteronomy | | Unisex | Hebrew |
| Oliver | The olive tree. The biblical olive tree symbolizes fruitfulness and beauty and dignity. Extending an olive branch signifies an offer of peace.
| Male | Latin |
| Ollie | Latin, olive tree | Male | English |
| Omaha | | Unisex | Hebrew |
| Orion | Son of Fire
| Male | Greek |
| Oscar | God's spear.
| Male | English |
| Paddy | Latin, noble, patrician | Male | Irish |
| Pagan | from the country, countryman | Male | English |
| Panda | A bear like Chinese mammal, with distinct black and white markings | Male | |
| Panther | A black leopard | Male | |
| Pasht | | Unisex | |
| Patsy | From Patricia - Well born maiden | Male | English |
| Paul | small | Male | Latin |
| Peekaboo | | Male | |
| Pepper | A spice or condiment. | Male | Sanskrit |
| Percy | | Male | |
| Pete | A rock. Form of Peter.
| Male | English |
| Peter | A rock. Peter the biblical fisherman and apostle had impulsive nature and rocklike faith. In Catholic tradition he is the first pope.
| Male | Greek |
| Pewter | | Unisex | |
| Pink Panther | | Unisex | Hebrew |
| Pinkle Purr | | Unisex | |
| Pippin | Name of a king
| Male | |
| Pixel | | Male | |
| Plato | broad-shouldered | Male | Greek |
| Pluto | The ninth and most distant planet from the sun | Male | |