| Acronym | Meaning |
| REPELS | Reemitted Positron Energy Loss Spectroscopy |
| IMPATT | Impact Avalanche Transit-time |
| SCR | Selective Catalytic Reduction |
| RTPM | Real-time Polarization Modulation |
| MUCT | Multiphase Unsaturated Zone Contaminant Transport Model |
| ERK | Extracellular Signal-regulated Kinase |
| FSGF | FREEON Symmetric Group Formulation (of Hartree-Fock Theory) |
| LASCR | Light-activated Silicon Controlled Rectifier |
| IIRF | Intergalactic IR Radiation Field |
| MSCE | Modified Semiclassical Exchange (aproxn. In Scattering Calcns.) |