| Acronym | Meaning |
| CIR | Corotating Interaction Region |
| MACE | Multi-Agent Computing Environment |
| MPSI | Member Of The Pharmaceutical Society Of Ireland |
| MS | Megasecond |
| COEA | Cost Operational Effectiveness Analysis (military) |
| SCN | Suprachiasmatic Nucleus |
| QC | Quality Control -Qu?bec (postal Symbol) -Queen's Counsel |
| NAF | NATO Architecture Framework -Naval Air Facility |
| PR | Public Relations -Puerto Rico (postal Symbol; ISO 3166 Digram) |
| MCSF | Marine Corps Security Forces |