| Acronym | Meaning |
| CNDO SP | Complete Neglect Of Differential Overlap Spin Polarization |
| CTL | Cytotoxic T Lymphocyte |
| NSOM | Near-field Scanning Optical Microscopy |
| HV | Vickers Hardness Number |
| PCS | Permit Compliance System |
| EISCAT | European Incoherent Scatter Radar (atm. Sensing) |
| GHO | Generalized Hybrid Orbital (ao) |
| RCTM | Regional Chemical Transport Model |
| PE | Population Equivalent (in Wastewater Treatment) |
| IUCN | International Union For Conservation Of Nature And Natural Resources |