| Acronym | Meaning |
| ITC | Interagency Testing Committee (TSCA) |
| CRS | Coordinate-representation Sudden (decoupling Method For Mol. Inelastic Collisions) |
| ICC | Intrahepatic Cholangiocarcinoma |
| IFAS | Integrated Fixed-film Activated Sludge |
| MTD | Maximum Tolerated Dose |
| CEPEX | Central Equatorial Pacific Experiment |
| ATRS | Attenuated Total Reflection Spectroscopy |
| HFS | Hartree Fock Slater |
| ISSI | International Society For Scientometrics And Informetrics |
| CEEL | Community Emergency Exposure Level |