| Mr | relative molecular mass |
|---|---|
| RF | radial fiber; radio frequency; receptive field; regurgitant fraction; Reitland-Franklin [unit]; rela... |
| RR | radiation reaction; radiation response; rate ratio; rational recovery [group]; recovery room; relati... |
| RSA | rabbit serum albumin; regular spiking activity; relative specific activity; relative standard accura... |
| BM | Bachelor of Medicine; barium meal; basal medium; basal metabolism; basement membrane; basilar membra... |