| REE | rapid extinction effect; rare earth element; resting energy expenditure |
|---|---|
| R-EEG | resting electroencephalography |
| REL | rate of energy loss; recommended exposure limit; resting expiratory level |
| RHR | renal hypertensive rat; resting heart rate |
| RME | rapid maxillary expansion; resting metabolic expenditure; right mediolateral episiotomy |