| Acronym | Meaning |
| SSB | Semiclassical Sudden Born (approxn. In Ion-atom Collisions) |
| OLF | Overland Flow |
| PDF | Probability-distribution Function |
| ANS | Advanced Neutron Source |
| RDA | Regularized Discriminant Analysis |
| Y-STR | Y Chromosome Short Tandem Repeat |
| PCD | Polycrystalline Diamond |
| PKI | Public Key Infrastructure |
| UNCED | United Nations Conference On Environment And Development |
| MR-L-CEPM | Multireference-linearized-coupled Electron Pair Method |