| RPS | renal pressor substance; revolutions per second |
|---|---|
| RQ | recovery quotient; [Hazardous Substance] Reportable Quantities [List]; reportable quantity; respirat... |
| RS | radioscaphoid; random sample; rating schedule; Raynaud syndrome; recipient's serum; rectal sinus; re... |
| Rst | in paper or thin layer chromatography, the distance that a spot of a substance has moved, relative t... |
| SAAS | Substance Abuse Attitude Survey |