| Acronym | Definition |
|---|
| MSSS | Ministère de la Santé et des Services Sociaux (French) |
| MSSS | Malin Space Science Systems |
| MSSS | Microsoft Security Summit |
| MSSS | Maui Space Surveillance System |
| MSSS | McMaster Social Sciences Society |
| MSSS | Magnox Swarf Storage Silo (UK) |
| MSSS | Multiple Sclerosis Society Scotland (UK) |
| MSSS | Minimum Statistical Sample Size |
| MSSS | My Super Sweet 16 (TV show) |
| MSSS | Medication Safety Support Service (Canada) |
| MSSS | Multi Stage Selector Switch |
| MSSS | Manpower Staffing Standards System |
| MSSS | Multi-Story Steel Structure |
| MSSS | Modular System Software Specification |
| MSSS | Maxtor Shared Storage Solution (networked data storage) |
| MSSS | Mudgeeraba State Special School (Australia) |