| Acronym | Meaning |
| PEDM | Perturbation Expansion (of The) Density Matrix |
| VGAAS | Vapor Generation Atomic Absorption Spectrometry |
| DEXA | Dual Energy X-ray Absorptiometry |
| ACH | Air Changes Per Hour |
| FDDI | Fiber-Distributed Data Interface |
| UMP2 | Unrestricted Moeller-Plesset 2nd-order (perturbation Theory) |
| AEMA | Auger Electron Microanalysis |
| CIIT | Chemical Industry Institute Of Toxicology |
| PWFB | Plane-wave First Born |
| WASP4 | Water Analysis Simulation Program |