| RNFP | Registered Nurse Fellowship Program |
|---|---|
| RNIB | Royal National Institute for the Blind |
| RNICU | regional neonatal intensive care unit |
| RNID | Royal National Institute for the Deaf |
| RNP | ribonucleoprotein |
| RNR | ribonucleotide reductase |
| RNS | reference normal serum; repetitive nerve stimulation; ribonuclease |
| RNS test | Repetitive Nerve Stimulation test |
| RNSC | radionuclide superior cavography |
| Rnt | roentgenology |