| Abbreviation | Definition |
|---|---|
| MSCC | Morgan Sports Car Club |
| MSCK | Motor Sport Club Königsbrunn |
| MSCM | Miniature Schnauzer Club of Michigan |
| MSDGC | Mitten State Disc Golf Club |
| MSFC | Melbourne Science Fiction Club |
| MSNBC | Mean Socialist Nasty Bully Club |
| MSSC | Mahomet Seymour Soccer Club |
| MSSC | Manayunk Sport And Social Club |
| MSSC | Manayunk Sport and Social Club's |
| MSSC | Maryland Suburban Swim Club |
| MSSC | Mississauga Sport and Social Club |
| MSSC | Muscle Shoals Sailing Club |
| MSURC | Manawatu Saddle Up Riding Club |
| MSYC | Mount Sinai Yacht Club |
| MT | Manual Transmission |
| MTC | Motor Touring Club |
| MTFC | Macclesfield Town Football Club |
| MTFC | Magno Twins Fans Club |
| MTFC | Mansfield Town Football Club |
| MTFC | Matlock Town Football Club |