| Acronym | Meaning |
| TSDIA | Two-scale Direct-interaction Approximation [in Flow Energy Modeling] |
| HTSUS | Harmonized Tariff System U.S. |
| DDM | Denuder Difference Method |
| BOP | Basic-O Process |
| MMI | Mucous Membrane Effects |
| ATR-FTIR | Attenuated Total Reflection-Fourier-transform IR Spectroscopy |
| CMB | Cosmic Microwave Background |
| EPS | Extrapyramidal Side Effect |
| DQC | Decagonal Quasicrystal |
| FRC | Free Residual Chlorine |