| Acronym | Definition |
|---|
| MSOS➣Multi Service over Sonet |
| MSOS➣Multiple Systems Operators |
| MSOS➣Medication Safety Officers Society (formerly American Society of Medication Safety Officers) |
| MSOS➣Manitoba Society of Seniors (est. 1979; Canada) |
| MSOS➣Marine Special Operations School (US Marine Corps) |
| MSOS➣Mouse Son of Sevenless (genetics) |
| MSOS➣Mass Storage Operating System |
| MSOS➣Mammalian Son of Sevenless (gene) |