Achternamen
| Achternaam | Aantal |
|---|---|
| Ohrem | 2 |
| Oichowiecki | 1 |
| Oidtmann | 2 |
| Oijen | 12 |
| Oijen, van | 63 |
| Oirbains | 1 |
| Oirbans | 11 |
| Oirboins | 1 |
| Oirbons | 12 |
| Oirschot | 2 |
| Oirschot, van | 21 |
| Oirschoy, van | 1 |
| Oisterwijk | 1 |
| Oitmann | 6 |
| Ojen, van | 1 |
| Okhuijzen | 1 |
| Okhuizen | 2 |
| Okhuysen | 3 |
| Okhuyzen | 1 |
| Okkerman | 2 |
| Okkerse | 3 |
| Olaerts | 10 |
| Olah | 1 |
| Olbers | 1 |
| Olberts | 1 |