| Acronym | Definition |
|---|
| MDSG➣Mood Disorders Support Group, Inc. |
| MDSG➣Myotonic Dystrophy Support Group (Carlton, England, UK) |
| MDSG➣Mineral Deposits Studies Group (Geological Society of London; UK) |
| MDSG➣Membership Development Support Grant (various agencies) |
| MDSG➣Missile Defense Support Group |
| MDSG➣Marketing Director's Support Group (forum) |
| MDSG➣Missile Defense Steering Group (Missile Defense Agency) |
| MDSG➣Market Development Services Group |