| OCC | object-centered coordinate [method]; oral cholecystography |
|---|---|
| OCG | omnicardiogram; oral cholecystogram |
| OCH | oral contraceptive hormone |
| OCM | oral contraceptive medication |
| OCS | occipital condyle syndrome; Ondine's curse syndrome; open canalicular system; oral contraceptive ste... |
| ROU | Recurrent oral ulcer |
|---|---|
| TOPV | Trivalent oral poliovaccine |
| PO | per oral |