| Acronym | Meaning |
| RUC | Royal Ulster Constabulary |
| EI | Ireland (FIPS 10-4 Country Code; From ire) |
| HMO | Hiri Motu Language (ISO 639-2 Code) |
| AT | Astatine |
| USR | Universal System Resources (/usr |
| VMN | VentroMedial Nucleus (neurophysiology) |
| PKM | Pulemet Kalashnikova Modernizirovanniy (Russian ??? ??????? ??????????? ????????????????? |
| SSM | Surface-to-Surface (Guided) Missile |
| JWST | James Webb Space Telescope |
| MITL | Man-In-The-Loop |