| Abbreviation | Definition |
|---|---|
| OMH | Otsego Memorial Hospital |
| OMM | Osteopathic Manipulative Medicine |
| OMNI | Opera Nazionale Maternita e Infanzia |
| OMSH-N | Olaniba Memorial & Specialist Hospital-Nigeria |
| OMT | Osteopathic Manipulative Therapy |
| ONH | Osaka National Hospital |
| ONS | Oncology Nursing Service |
| OOB | Out Of Bed |
| OOPD | Orthop(a)edic Out-Patient Department |
| OOPD | Orthopedic Out-Patient Department |
| OOR | Orthopedic Operating Room |
| OOT | Out Of Trend |
| OOTC | Out Of The Crisis |
| OOTW | Out Of The Woods |
| OP | Off Pump |
| OP | On Program |
| OP | Operative Procedure |
| OPAQ | OsteoPorosis Assessment Questionnaire |
| OPAT | Outpatient Parenteral Antibiotic Therapy |
| OPBH | Out-Patient Behavioral Health |