| reg | region; regular |
|---|---|
| RMSCR | rhabdomyosarcoma chromosomal region |
| ROI | reactive oxygen intermediate; region of interest; right occipitolateral [fetal position] |
| SMCR | Smith-Magenis chromosome region |
| SRO | sex-ratio organism; single room occupancy; smallest region of overlap; Steele-Richardson-Olszewski [... |