| Acronym | Meaning |
| PRDDO | Partial Retention Of Diatomic Differential Overlap |
| GEP | Good Engineering Practice |
| SO | Stieltjes Orbitals (for Mol. Photoionization Continua) |
| TPCA | Toxic Pit Cleanup Act (of California |
| PGP | Previous Glacial Period (glacial Maximum Of O18 Stage 6; Predates The LGM) |
| PQC | Piezoelectric Quartz Crystal |
| LMR | Laser Magnetic Resonance |
| BRET | Bioluminescence Resonance Energy Transfer |
| MP-QMC | Model Potential-quantum Monte Carlo |
| APD | Action Potential Duration |