| Name | Meaning | Gender | Origin |
|---|
| Onyx | A gemstone with bands of different colours. | Unisex | English |
| Oreo | American cookie brand consisting of two chocolate wafers with white cream filling. | Unisex | English |
| Panda | A bear like Chinese mammal, with distinct black and white markings | Unisex | English |
| Pandora | All gift | Female | Greek |
| Panther | A black leopard | Unisex | English |
| Pasha | Passover | Unisex | Greek |
| Patches | | Unisex | Hebrew |
| Patsy | A patrician | Female | Latin |
| Patty | A patrician | Female | Latin |
| Peaches | Red, yellow skinned fleshy fruit | Unisex | English |
| Peanut | Edible nuts eaten raw or roasted. | Unisex | English |
| Pearl | Pearl | Female | English |
| Pebbles | After the character in 'The Flintstones' cartoons | Female | English |
| Penny | Weaver | Female | Greek |
| Pepe | He will enlarge | Unisex | Hebrew |
| Pepper | Pepper | Female | English |
| Peppy | | Unisex | Hebrew |
| Pepsi | Brand of cola soft drink. | Unisex | English |
| Petey | Stone | Unisex | Greek |
| Phantom | Something elusive. A ghost | Unisex | English |
| Phoebe | Bright | Female | Greek |
| Picasso | | Unisex | Hebrew |
| Pickles | Food flavored in a solution of vinegar | Unisex | English |
| Piggy | | Unisex | Hebrew |
| Piglet | | Unisex | Hebrew |
| Pinky | For Pinky Lee, the painting, and the color of her nose | Unisex | English |
| Piper | A pipe player | Female | English |
| Pippin | Foreigner, stranger | Unisex | Latin |
| Pirate | | Unisex | Hebrew |
| Pixie | A fairy like creature. Playful and mischievous | Female | English |