| Oligurie | oliguria |
| Ligurien | Liguria |
| Oligarch | oligarch |
| Oligarchie | oligarchy |
| Uigurin | Uyghur |
| Figurine | figurine |
| Uigure | Uighur Uyghur |
| Oxalurie | oxaluria |
| Polyurie | polyuria |
| Lingerie | lingerie |
| Oviparie | oviparity |
| Olivia | Olivia |
| Olivin | olivine |
| Polierin | foreperson |
| Voliere | aviary |
| Volière | aviary |
| oligozän | Oligocene |
| Oligozän | Oligocene |
| Kolibri | hummingbird |
| Oligomer | oligomer |