| Acronym | Meaning |
| IIRS | Ion Impact Radiation Spectroscopy |
| RAS | Returned Activated Sludge |
| AMSA | Association Of Metropolitan Sewerage Agencies |
| LRTAP | Long-range Transboundary Air Pollution |
| XMLD | X-ray Magnetic Linear Dichroism |
| MFA | Molecular-field Approximation |
| ORSTB | Overlap-reduced Semiempirical Tight-binding |
| CCLGO | Catalytic Cracked Light Gas Oil |
| RIFT | Resin Infusion Under Flexible Tooling [plastics Molding] |
| HATR | Horizontal Attenuated Total Reflection |