| RER | Rough Endoplasmic Reticulum |
|---|---|
| RER | renal excretion rate; respiratory exchange ratio; rough endoplasmic reticulum |
| RNA | radionuclide angiography; Registered Nurse Anesthetist; ribonucleic acid; rough, noncapsulated, avir... |
| SR | sarcoplasmic reticulum; saturation recovery; scanning radiometer; screen; secretion rate; sedimentat... |
| S-R | smooth-rough [bacteria] |