| Acronym | Meaning |
| TBA | Tight Binding Approximation |
| STLC | Soluble Threshold Limit Concentration |
| EH | Extended Hueckel |
| MSO | Maximum Similarity (spin) Orbital |
| FP | Fluorescence Polarizationpar |
| ECE | Electrical Conductivity Of Saturation Extract (soils) |
| IPPA | Independent Pair-potential Approximation |
| ABWR | Advanced Boiling Water Reactor |
| DWPO | Distorted Wave Polarized Orbital |
| CEH | Cholesteryl Ester Hydrolase |