| Abbreviation | Definition |
|---|---|
| MSS | Medical Superintendents Society |
| MSS | Medical Superintendents’ Society |
| MSSA | Malaysian Singaporean Students Association |
| MSSA | Maryland Saltwater Sportfishermens Association |
| MSSA | Mid South Sociological Association |
| MSSA | Mormon Social Science Association |
| MSSA | Mssamanoa School Student Association |
| MSSS | Malaysian Society of Soil Science |
| MSSS | Manitoba Soil Science Society |
| MST | Minimal Standard Terminology |
| MSTA | Manufacturers Surgical Trade Association |
| MSTA | Maryland State Teachers Association |
| MSTA | Michigan Science Teachers Association |
| MSTA | Michigan Septic Tank Association |
| MSTA | Missisippi Science Teachers Association |
| MSTA | Missouri State Teachers Association |
| MSTB | Malaysian Software Testing Board |
| MSTG | Material Safety Task Group |
| MSTS | MusculoSkeletal Tumor Society |
| MSTT | Midwest Society for Trenchless Technology |