| Abbreviation | Definition |
|---|---|
| RSR | Real Space R-factor |
| RSV | Reduced Specific Viscosity |
| RT | Reagent Type |
| RT | Room Temperature |
| RTA | Rubidium Titanyl Arsenate |
| RTD | Relative Temperature Device |
| RTECS | Registry Of Toxic Effects Of Chemical Substances |
| RTP | Room Temperature and Pressure |
| RTPW | Resistance at the Triple Point of Water |
| RTV | Room Temperature Vulcanizer |
| RTV | Room Temperature Vulcanizing |
| Ru | Ruthenium |
| RUO | Ruthenium Oxide |
| RV | Realized Volatility |
| RV | Reduced Viscosity |
| RV | Referenced Variable |
| RVD | Regulatory Volume Decrease |
| RVP | Reid Vapor Pressure |
| RXNS | Reactions |
| S | Saturating |