| Acronym | Meaning |
| CERCLA | Comprehensive Environmental Response |
| CAST | Cyclic Activated Sludge Technol. |
| ARA | Aggregate Risk Analysis |
| MAM | Modified Atoms (in) Molecules |
| EDPCR | Extended Disjoint Principal Components Regression |
| NTB | Nonorthogonal Tight-binding |
| DRPA | Direct Random Phase Approximation |
| ALAP | As Low As Possible |
| DECENT | Distribution Of Exact Classical Energy Transfer Approximation |
| MFC | Multiconfigurational Frozen Core (approxn. For Electron-atom Scattering Calcns.) |