| Acronym | Meaning |
| TRLFS | Time Resolved Laser Fluorescence Spectroscopy |
| TRLIF | Time-resolved Laser-induced Fluorescence |
| TRM | Thermoremanent Magnetization |
| TRMM | Tropical Rainfall Measuring Mission |
| TRNA | Transfer Ribonucleic Acid |
| TRNOE | Transferred Nuclear Overhauser Effect |
| TRO | Tubular Reverse Osmosis |
| TROESY | Transverse Rotating-frame Overhauser Effect Spectroscopy |
| TROLL | Transmitter And Receiver Of Laser Light |
| TROLS | Terrestrial And Riparian Organisms |
| TROSY | Transverse Relaxation-optimized Spectroscopy |
| TRPH | Total Recoverable Petroleum Hydrocarbons |
| TRPO | Trialkylphosphine Oxide |
| TRRFC | Time-resolved Radio Frequency Conductivity |
| TRRS | Time-resolved Raman Spectroscopy |
| TRS | Total Reduced Sulfur |
| TRS | Transverse Rupture Strength |
| TRSERS | Time-resolved Surface Enhanced Raman Spectroscopy |
| TRUEX | Transuranic Extraction |
| TRXF | Total Reflection X-ray Fluorescence |
| TRXPS | Total Reflection X-ray Photoelectron Spectroscopy |
| TRXRD | Time-resolved X-ray Diffraction |
| TS | Transition State |
| TSA | Temperature Swing Adsorption |
| TSA | Thermal Swing Adsorption |
| TSA | Toluenesulfonic Acid |
| TSA | Trichostatin A |
| TSAE | Two-state Atomic Expansion (model For Atom-ion Collisions) |
| TSC | Thermal Stimulated Current |
| TSCA | Toxic Substances Control Act |
| TSCAP | Thermally Stimulated Capacitance |
| TSCATS | Toxic Substances Control Act Test Submissions Online Database |
| TSCW | Torsional Spin Current Wave (type Of Hartree-Fock Wave Function) |
| TSD | Technical Support Document |
| TSD | Thermally Stimulated Discharge |
| TSD | Treatment, Storage, Or Disposal |
| TSDC | Thermally Stimulated Depolarization Currents |
| TSDF | Treatment, Storage, And Disposal Facility |
| TSDIA | Two-scale Direct-interaction Approximation [in Flow Energy Modeling] |
| TSDRF | Treatment, Storage, Disposal, And Recycling Facilities |
| TSDW | Torsional Spin Density Wave |
| TSE | Transmissible Spongiform Encephalopathies |
| TSEE | Thermally Stimulated Exoelectron Emission |
| TSETG | Two-step Excitation Transient Grating |
| TSFZ | Traveling Solvent Floating Zone |
| TSG | Tumor Suppressor Gene |
| TSH | (classical) Trajectory Surface Hopping (for Ion-mol. Collisions) |
| TSH | Tensor Surface Harmonic (method In Bonding Of Metal Clusters) |
| TSH | Thyroid-stimulating Hormone |
| TSI | Trophic State Index |