| Acronym | Meaning |
| UDI | Utility Data Institute (power Generation) |
| PKA | Protein Kinase A |
| LMIS | Liquid Metal Ion Source |
| SPA | Shielded-potential Approxn. (in Electronic Structure) |
| EEPROM | Elec. Erasable-programmable Read-only Memory |
| MRCC | Multireference Coupled Cluster |
| TSH | (classical) Trajectory Surface Hopping (for Ion-mol. Collisions) |
| AJCC | American Joint Committee On Cancer |
| BSCO | Break Specific Carbon Monoxide |
| AQDHS | Air Quality Data Handling System |