| Acronym | Meaning |
| POA | Preoptic Area |
| TSD | Treatment, Storage, Or Disposal |
| QC-SCF | Quadratically Convergent SCF (for Closed-shell Systems) |
| CHA | Concentric Hemispherical Analyzer |
| HSWA | Hazardous And Solid Waste Amendments Of 1984 |
| IGAC | International Global Atmospheric Chemistry |
| IFD | Industrial Facilities Discharge File (file Within STORET) |
| UNECE | United Nations Economic Commission For Europe |
| TDM | Time-division Multiplexing |
| CCMC-T2 | Coupled-cluster Multiconfigurational (double-excitation Method With Cluster Operator Approximated By T2) |