| RN | radionuclide; red nucleus; Registered Nurse; registry number; residual nitrogen; reticular nucleus |
|---|---|
| ROC | receiver operating characteristic; receptor-operated channels; relative operating characteristic; re... |
| RRF | residual renal function |
| RU | radioulnar; rat unit; reading unit; residual urine; resin uptake; resistance unit; retrograde urogra... |
| RUV | residual urine volume |