| Acronym | Meaning |
| RCO | Regenerative Catalytic Oxidizer |
| PRRSV | Porcine Reproductive And Respiratory Syndrome Virus |
| ELLAP | Environmental Lead Laboratory Accreditation Program |
| RCHF | Relaxed-core Hartree-Fock (approxn. In Calcns. On Mol. K-shell Excitation Spectra) |
| FGFR | Fibroblast Growth Factor Receptor |
| RGB | Red Giant Branch (star) |
| QCPE | Quantum Chemistry Program Exchange |
| DMICS | Design Methods For Integrated Control Systems [propulsion] |
| FRAP | Fluorescence Recovery After Photobleaching |
| SAC | Symmetry-adapted Cluster (expansion Method For Calcg. Wave Functions) |