| Acronym | Meaning |
| PTC | Positive Temperature Coefficient [elec. Conducting Material] |
| MPE | Mean Percent Error |
| PBO | Polarized Born-Oppenheimer |
| RAPIDS | Regional Air Pollutant Inventory Development System |
| ELH | Egg-laying Hormone |
| REELS | Reflection Electron Energy-loss Spectroscopy |
| BOCLE | Ball-on Cylinder Lubricity Evaluator |
| XRCF | X-ray Calibration Facility |
| AACG | American Association For Crystal Growth |
| TTFA | Target Transformation Factor Analysis |