| Abbreviation | Definition |
|---|---|
| OOS | Occupational Overuse Syndrome |
| OP | Occiput Posterior |
| OP | Occlusal Plane |
| OP | Open Palm |
| OP | OPeration |
| OP | Organising Pneumonia |
| OP | OroPharyngeal |
| OP | OroPharynx |
| OP | OsteoPorosis |
| OP | Out-Patient |
| OPA | OroPharyngeal Airway |
| OPC | OroPharyngeal Candidiasis |
| OPC | OutPatient Clinic |
| OPD | Obnoxious Personality Disorder |
| OPD | Officially Pronounced Dead |
| OPD | Out-Patient Department |
| OPG | OhioHealth Physician Group |
| OPG | Osteoprotegerin |
| OPHTH | Ophthalmology |
| OPI | Ophthalmic Physicians Inc |