| Acronym | Meaning |
| RERS | Resonance-enhanced Raman Scattering |
| RESA | Ring Infected Erythrocyte Surface Antigen |
| RESAM | Regional Soil Acidification Model |
| RESIS | Receptor Site Interaction Simulation |
| RESOLVE | Research On Operations Limiting Visual Extinction |
| RESS | Rapid Expansion Of Supercritical Solution |
| RET | Resonance Energy Transfer |
| REV | Ray Eigenvector (a Wave Function) |
| REX | Reactive Extrusion |
| REX | Relativistically Parametrized Extended Hueckel |
| RF | Response Factor |
| RFA | RCRA Facility Assessment |
| RFA | Regulatory Flexibility Act |
| RFA | Regulatory Flexibility Analysis |
| RFA | Renormalized Free Atom (model |
| RFA | Retarding Field Analyzer |
| RFB | Recycle Fluidized-bed |
| RFBCM | Random-field Blume-capel Model (hamiltonian For Magnetic System) |
| RFC | Inhalation Reference Concentration |
| RFCC | Residue Fluid Catalytic Cracking |
| RFCCU | Residue Fluid Catalytic Cracking Unit |
| RFD | Reference Dose |
| RFDR | Radiofrequency-driven Dipolar Recoupling |
| RFE | Recursive Feature Elimination |
| RFE | Relative Fit Error |
| RFE | Relaxor Ferroelectrics |
| RFEC | Remote Field Eddy Current |
| RFETS | Rocky Flats Environmental Technology Site |
| RFG | Reformulated Gasoline |
| RFGD | Radio-frequency Glow Discharge |
| RFGE | Rotating-field Gel Electrophoresis |
| RFI | RCRA Facility Investigation |
| RFI | Radio Frequency Interference |
| RFIC | Radio Frequency Integrated Circuit |
| RFID | Radio-frequency Identification |
| RFIE | Reverse Flow Ion Exchange |
| RFL | Resorcinol-formaldehyde Latex [dip Coating] |
| RFLP | Restriction Fragment Length Polymorphism |
| RFM | Relativistic Mean Field |
| RFM | Rotating Magnetic Field |
| RFP | Reasonable Further Progress |
| RFPS | Radio-frequency Plasma Spraying |
| RFQ | Radio-frequency Quadrupole |
| RFT | Respirator Fit Test |
| RFWM | Resonant Four-wave Mixing |
| RGA | Residual Gas Analysis |
| RGB | Red Giant Branch (star) |
| RGC | Retinal Ganglion Cell |
| RGS | Regulator Of G-protein Signaling |
| RGTO | Rheotaxial Growth And Thermal Oxidation |