| Termen/ Term | Nr. apariții/ No. occurrences |
| Ocna Șugatag | 1 |
| Octavian, Oana | 1 |
| Odaia | 3 |
| Odobești | 5 |
| Odorhei | 127 |
| Odovinca, Floarea | 2 |
| Odovinca, Ioana | 1 |
| Ogrezeanu, Aurelia | 7 |
| Ogrezeanu, Elisabeta | 3 |
| Ogrezeanu, Gheorghe | 1 |
| Ogrezeanu, Stelian | 68 |
| Ogrezeanu, Victor | 17 |
| Ohada, Adela | 2 |
| Ohan | 1 |
| Ohaza | 1 |
| Ola, Iozef | 1 |
| Olărașu, Ion | 2 |
| Olariu, Gheorghe N. | 1 |
| Olariu, Ion | 1 |
| Olariu, Verona | 2 |
| Olaru Mila, Ion | 1 |
| Olaru, Ana | 1 |
| Olaru, Angela | 3 |
| Olaru, Eleonora | 6 |
| Olaru, Gheorghe | 3 |
| Olaru, Ion | 1 |
| Olaru, Raluca | 2 |
| Olaru, Safta | 1 |
| Olaru, Serafima | 2 |
| Olecsiuc, Vasile | 1 |
| Olenici, Eugenia | 1 |
| Olenici, Veronica | 4 |
| Oleniuc, Veronica | 4 |
| Olesniuc, Alexandru | 1 |
| Olici, Eudochia | 1 |
| Olinici, Eugenia | 5 |
| Olom, Ioan | 1 |
| Olt | 710 |
| Oltean, Ana | 1 |
| Oltean, Grigore | 3 |
| Oltean, Ion | 4 |
| Oltean, Simion | 1 |
| Olteanu, Ecaterina Viorica | 1 |
| Olteanu, Eleonora | 1 |
| Olteanu, Elisabeta | 1 |
| Olteanu, Floarea | 1 |
| Olteanu, Grigore | 1 |
| Olteanu, Ioan | 1 |
| Olteanu, Ion | 79 |
| Olteanu, Lilica | 2 |