| Acronym | Meaning |
| SECI | Single Excitation Configuration Interaction |
| BODC | Born-Oppenheimer Diagonal Correction (in Mol. Calcns.) |
| GLISP | Great Lakes International Surveillance Plan |
| SEMC | Scaled Ensemble Monte Carlo |
| UMP | Uridine 5'-phosphate |
| NME | New Molecular Entity |
| IWKB | Iterated Wentzel-Kramers-Brillouin |
| QBO | Quantitative Basis Orbital (an MO Or AO) |
| KVP | Kohn Variational Principle |
| RAS | Returned Activated Sludge |