| Acronym | Meaning |
| HCI | Highly Charged Ion |
| ZEV | Zero Emission Vehicle |
| CVB | Canonical Valence Bond |
| PMP2 | (spin) Projected Moeller-Plesset Second-order (perturbation Theory) |
| SDA | Subsurface Disposal Area |
| EPSP | Excitatory Postsynaptic Potential |
| UTLA | Ultra Thin Layer Activation |
| 2PH TDA | Two-particle-hole Tamm-Dancoff Approximation (for Closed-shell |
| OS | Overlapping Spheres (method) |
| ECHIC | Evaporative Compact High-intensity Cooler |