| Acronym | Meaning |
| PTRI | Programmed Temperature Retention Index |
| PSEP | Polyhedral Skeletal Electron Pair (for Metal Clusters) |
| RDH | Rapid Displacement Heating (pulping - For Paper) |
| CWM | Center For Waste Management |
| FEA | Finite-element Analysis |
| FOE | First-order Exchange (in Electron-atom Scattering Calcn.) |
| ENDF | Evaluated Nuclear Data File |
| SMSX(ALPHA) | Overlapping-sphere Multiple-scattering X(alpha) |
| ISO | IR Space Observatory |
| MAT | Microactivity Tests |