| Acronym | Meaning |
| IFFD | Intermittently Fed Fill And Draw System |
| NEIC | National Enforcement Investigations Center |
| ESA | Electrokinetic Sonic Amplitude |
| TLV | Threshold Limit Value |
| ECF | Electric Crystal Field |
| HOHAHA | Homonuclear Hartman-Hahn Spectroscopy |
| ECI | Size-extensive CI |
| DMRG | Density Matrix Renormalization Group (quantum Calcn. Method) |
| ARC | AIDS-related Complex |
| LRTAP | Long-range Transboundary Air Pollution |