| Acronym | Meaning |
| AEM | Analytical Electron Microscopy |
| PCM | Phase-change Material (in Heat Storage) |
| PBM | Peripheral Blood Monocyte |
| ASTM | American Society For Testing And Materials |
| ARF | ADP-ribosylation Factor |
| AU | Absorbance Units |
| ORI | Octane Requirement Increase |
| IIRF | Infinite Impulse Response Filter |
| PBM | Photochem. Box Model |
| IAPA | Independent Asymptotic Pair Approxn. (in Electronic Structure) |