| Name | Meaning | Gender | Origin |
|---|
| Oleander | | Unisex | |
| Olive | kind one; olive tree, peace. Symbol of peace. A small oval fruit. | Female | English |
| Olivia | Olive
| Female | Latin |
| Opal | Australian gemstone of remarkable colours, usually red, blue or green | Female | Sanskrit |
| Opal | Australian gemstone of remarkable colours, usually red, blue or green | Female | Sanskrit |
| Orange | Round citrus fruit originating in Southeast Asia. | Female | Fruit |
| Orange | Round citrus fruit originating in Southeast Asia. | Female | Fruit |
| Orchid | | Female | |
| Osceola | | Unisex | Hebrew |
| Pandu | | Unisex | |
| Peach | | Unisex | |
| Pearl | Precious jewel. A hard, rounded gem, usually white in colour | Female | Latin |
| Penny | Greek, weaver | Female | English |
| Petunia | trumpet-shaped flower | Female | English |
| Phantom | Something elusive. A ghost | Unisex | |
| Phyllis | A green branch.
| Female | Greek |
| Pink | | Female | |
| Pinky | For Pinky Lee, the painting, and the color of her nose | Unisex | |
| Plum | | Female | |
| Popcorn | Corn that when heated forms white edible puffs. | Unisex | |
| Poppy | Flower with four crumpled petals in red, orange or white colours | Female | Latin |
| Poppy | Flower with four crumpled petals in red, orange or white colours | Female | Latin |
| Powder | Substance of fine particles. Light, dry snow. | Unisex | |
| Primrose | first rose | Female | English |
| Prune | A partially dried plum. | Female | Fruit |