| Acronym | Meaning |
| APSG | Antisymmetrized Product Of Separated Geminals |
| ISSC | International Subcommission On Stratigraphic Classification |
| ELLPAT | Environmental Lead Laboratory Proficiency Analytical Testing |
| IVA | Intravehicular Activity (related To Spacecraft) |
| SNS | Sympathetic Nervous System |
| EDF | Energy Density Functional (theory In Electronic-property Calcn.) |
| HNC | Hypernetted Chain |
| IHSS | International Humic Substances Society |
| HDD | Halogenated Dibenzodioxin(s) |
| AAR | Alkali-aggregate Reaction |