| 1 | English | stander | One who stands; A standel |
| 2 | English | stand | "To position or be positioned physically."; "To... |
| 3 | English | op | An operation; An amateur radio operator; An... |
| 4 | English | op shop | A shop, usually operated by a charity, to which... |
| 5 | English | opportunity | A chance for advancement, progress or profit; A... |
| 6 | English | opportune | Suitable for some particular purpose; At a... |
| 7 | Middle French | opportunité | — |
| 8 | Latin | opportūnitās | — |
| 9 | Latin | opportūnus | — |
| 10 | Latin | Portus | — |
| 11 | Proto-Italic | portus | harbour |
| 12 | Proto-Indo-European | pértus | crossing |
| 13 | Proto-Indo-European | per- | before, in front; first; to go through |
| 14 | Proto-Indo-European | pr̥tós | passed , crossed |