| Acronym | Meaning |
| OTE | Oxygen Transfer Efficiency (of Aeration Diffusers) |
| MLEE | Multilocus Enzyme Electrophoresis |
| ENA | Energetic Neutral Atoms (astronomical Plasmas) |
| GCO | General Coupling Operator (in Calcns. Of Vector Coupling For Atoms And Ions) |
| LSV | Linear Sweep Voltammetry |
| IVAP | Intimate Valence Alternation Pairs (bonding Model In Electronic Structure Calcns.) |
| MRL | Maximum Residue Limit |
| GRI | Geosynthetics Research Institute (Drexel University |
| PPKTP | Periodically Poled KTiOPO4 |
| EFRTS | External-floating-roof Tanks |