| Abbreviation | Definition |
|---|---|
| MSSO | MedDRA Maintenance and Support Services Organization |
| MSSR | McCormick Schmicks Seafood Restaurant |
| MSSS | Magda Svenssons Skeppshandel Sweden |
| MSSS | Malin Space Science Systems |
| MST | Massif Software Technologies |
| MSTA | Mink Security Training Advice |
| MSTA | Mink Security Training & Advice |
| MSTA | Moore Stephens Technology Australia |
| MSTB | Mechanical Systems Testing and Balancing, Inc. |
| MSTC | Maharashtra State Textile Corporation |
| MSTC | Manchester Suburban Tramways Company |
| MSTC | Midwestern Securities Trading Company |
| MSTG | Manufacturing Science and Technology Group |
| MSTH | Malaysia Software Testing Hub |
| MSTI | Mountain States Transmission Inter-tie |
| MSTS | Marine Support & Training Service |
| MSTT | Mark Smith Technical Training |
| MSU | Miaka Sites United |
| MSV | Mercury Special Vehicles |
| MSV | Mobile Satellite Ventures |