| Acronym | Meaning |
| RSMR | Rayleigh Scattering Of Moessbauer Radiation |
| PREM | Preliminary Ref. Earth Model |
| SQF | Second-quantized Formulation (in Many-body Quantum Theory) |
| SPECT | Single Photon Emission Computerized Tomography |
| EPOCA | Environmental Project On Central America |
| DIPPR | Design Institute For Physical Property Data |
| SLR | Spin-lattice Relaxation |
| TCR | T Cell Receptor |
| IEG | Immediate Early Gene |
| DTUL | Deflection Temperature Under Load |