| Acronym | Meaning |
| UAMO | Unprojected Alternant Molecular Orbital |
| LCOPW | Linear Combination Of Orthogonalized Plane Waves |
| ICBN | International Code Of Botanical Nomenclature |
| TOP | Trioctyl Phosphate |
| UHMWPE | Ultra High Molecular Weight Polyethylene |
| FILOS | Far Infrared Limb Observing Spectrometer |
| HABR | Hybrid Anaerobic Baffled Reactor (for Wastewater Treatment) |
| ECISDT | Size-extensive CI With Single And Double And Triple Excitations |
| GRO | Gasoline-range Organics |
| OVGF | Outer-valence Green Function (for Ionization-energy Calcns.) |