| Acronym | Meaning |
| SF-PNM | Step Function Perturbative Numerical Method |
| SF1 | Steroidogenic Factor 1 |
| SFA | Saturated Fatty Acid |
| SFA | Segmented Flow Analysis |
| SFA | Surface Force Apparatus |
| SFC | Specific Fuel Consumption |
| SFC | Supercritical Fluid Chromatography |
| SFCCCC | Space-fixed Complex-coordinate Coupled-channel Method |
| SFE | Stacking Fault Energy |
| SFE | Supercritical Fluid Extraction |
| SFEM | Scanning Field Emission Microscopy |
| SFF | Solid Freeform Fabrication |
| SFFF | Sedimentation Field Flow Fractionation |
| SFG | Sum Frequency Generation Spectroscopy |
| SFIP | Sector Facility Indexing Project |
| SFM | Scanning Force Microscopy |
| SFMS | Sector Field Mass Spectrometry |
| SFORD | Single Frequency Off Resonance Decoupling |
| SFR | Star Formation Rate |
| SFRC | Spruce-Fir Research Cooperative |
| SFRI | Sludge Filtration Resistance Index |
| SFRP | Stable Free Radical Polymerization |
| SFRS | Spin-flip Raman Scattering |
| SFS | Saybolt Furol Seconds |
| SFS | Sum-frequency Spectroscopy |
| SFV | Semliki Forest Virus |
| SGA | Soluble-gas Atomization |
| SGA | Symmetric Group Approach |
| SGBD | Steam Generator Blowdown |
| SGCR | Subcommittee Global Change Research |
| SGF | Spherical Gaussian Function |
| SGFET | Suspended Gate Field-effect Transistor |
| SGFM | Surface Green Function Matching (method In Calcn. Of Electronic And Phonon Properties Of Crystal Surfaces And Interfaces) |
| SGGA | Symmetric Group Graphical Approach (in CI Calcns.) |
| SGHWR | Steam-generating Heavy Water Reactor |
| SGM | Scale Glass Melter |
| SGMP | Sol-gel-microsphere Pelletization |
| SGO | Spherical Gaussian Orbital |
| SGOT | Serum Glutamic-oxaloacetic Transaminase |
| SGPR | Specific Gas Production Rate |
| SGPT | Serum Glutamic-pyruvic Transaminase |
| SGR | Steam Gas Recycle (process For Shale Oil Recovery) |
| SGTF | Spherical Gaussian-type Function |
| SGWD | Submarine Groundwater Discharge |
| SH2 | Src-homology 2 |
| SH3 | Src Homology 3 |
| SHADOZ | Southern Hemisphere Additional Ozone Sounding Program |
| SHAPE | Simulation Of Human Activity And Pollution Exposure |
| SHAPM | Shear Horizontal Acoustic Plate Mode |
| SHBG | Sex Hormone-binding Globulin |