| Acronym | Meaning |
| LQG | Linear Quadratic Gaussian |
| APFU | Atoms Per Formula Unit |
| GDR | Geophysical Data Record |
| NEAR | Near Earth Asteroid Rendezvous |
| EXFAS | Extended Fine Auger Structure |
| RFCC | Residue Fluid Catalytic Cracking |
| ABHP | American Board Of Health Physics |
| IRES | Infrared Emission Spectroscopy |
| ECM | Embedded Cluster Method (in Electronic-structure Calcns.) |
| TEDS | Timed Exposure Diffusive Sampler (for Air Pollution) |