| ORN | operating room nurse; orthopedic nurse |
|---|---|
| ORT | object relations technique; operating room technician; oral rehydration therapy |
| PAR | participating provider; passive avoidance reaction; perennial allergic rhinitis; photosynthetically ... |
| PARR | postanesthesia recovery room |
| RH | radiant heat; radiation hybrid; radiological health; reactive hyperemia; recurrent herpes; regulator... |