| ORS | olfactory reference syndrome; oral rehydration solution; oral surgery, oral surgeon; Orthopaedic Res... |
|---|---|
| RBA | relative binding affinity; rescue breathing apparatus; right basilar artery; right brachial artery; ... |
| RIRB | radioiodinated rose bengal |
| OCP | octacalcium phosphate; ocular cicatricial pemphigoid; oral case presentation; oral contraceptive pil... |
| OET | oral endotracheal tube; oral esophageal tube |