| Termen/ Term | Nr. aparižii/ No. occurrences |
| ODOBESTI | 1 |
| ODRIHEI | 1 |
| OGRADENA | 9 |
| OGRETIN | 1 |
| OHABA | 45 |
| OHABA DE SUB PIATRA | 1 |
| OHABA PONOR | 1 |
| OHABA STREIULUI | 1 |
| OHABA-MITMIC | 1 |
| OHABA-PONOR | 1 |
| OHABA-SIBISEL | 1 |
| OHABITA | 1 |
| OLARI | 8 |
| OLTEANCA | 2 |
| OLTEANU | 1 |
| OLTENI | 1 |
| OLTET | 12 |
| OLTINA | 1 |
| ONCESTI | 21 |
| ONEAGA | 2 |
| ORASANI | 1 |
| ORASTIOARA DE JOS | 138 |
| ORASTIOARA DE SUD | 1 |
| ORASTIOARA DE SUS | 2 |
| ORATIA | 2 |
| ORBEASCA | 1 |
| ORBEASCA DE SUS | 2 |
| ORBENII DE SUS | 1 |
| OREAVU | 1 |
| ORLASTI | 1 |
| ORLEA | 2 |
| ORLESTI | 1 |
| OROIU | 5 |
| OROSIA | 7 |
| ORSOVA | 198 |
| ORTOAIA | 1 |
| ORZESTI | 1 |
| OSASEL | 1 |
| OSICA DE SUS | 1 |
| OSMANCEA | 6 |
| OSOI | 1 |
| OSTRA | 1 |
| OSTROV | 3 |
| OSTROVU MARE | 2 |
| OTETELISU | 1 |