| RAG-1 | Recombination Activating Gene-1 |
|---|---|
| RAG-2 | Recombination-activating gene-2 |
| RAGE | Receptor for AGE |
| RAGE | Receptor for Advanced Glycation Endproduct |
| RAI | Radioactive iodine |
| RAI | Resident Assessment Instrument |
| RAI | Ritchie Articular Index |
| RAID | Radioimmunodetection |
| RAIR | recto anal inhibitory reflex |
| RAIT | Radioimmunotherapy |