| Acronym | Definition |
|---|
| MSSU➣Missouri Southern State University (Joplin) |
| MSSU➣Medical-Surgical Stepdown Unit (healthcare) |
| MSSU➣Moscow State Social University |
| MSSU➣Microsoft Services University |
| MSSU➣Management Selection & Succession Unit (HM Prison Service; UK) |
| MSSU➣Mid Stream Specimen Urine |
| MSSU➣Mid Stream Sample of Urine |