| Acronym | Meaning |
| HEDS | Human Exploration And Development Of Space |
| QDM | Quantum Defect Method |
| AQUIRE | Aquatic Information Retrieval |
| NNDO | Neglect Of Nonbonded Differential Overlap |
| THFFF | Thermal Field-flow Fractionation |
| CAI | Computer Aided Instruction |
| IRR | Internal Rate Of Return |
| ECBM | Extended Classical Over-barrier Model (in Calcns. On Inelastic Ion-atom Colisions) |
| EAS | Extensive Air Shower |
| BSE | Bulk Silicate Earth |