| MRU | mass radiography unit; minimal reproductive unit |
|---|---|
| RAD | radial artery catheter; radiation absorbed dose; radical; radiography or radiographic; reactive airw... |
| RT(R)(ARRT) | Registered Technologist, Radiography certified by the American Registry of Radiologic Technologists)... |
| SP | sacroposterior; sacrum to pubis; salivary progesterone; schizotypal personality; semi-private [room]... |
| Spr | scan projection radiography |