| Abbreviation | Definition |
|---|---|
| MDSL | Metro Detroit Soccer League |
| MESL | Manchester East Soccer League |
| MGSC | Monona Grove Soccer Club |
| MISA | Missoula Indoor Soccer Arena |
| MISL | Major Indoor Soccer League |
| MISL | Metropolitan Indoor Soccer League |
| MJSC | Miracle Junior Soccer Club |
| MKSC | Manhattan Kickers Soccer Club |
| MKSC | Melbourne Knights Soccer Club |
| MKSC | Milwaukee Kickers Soccer Club |
| MLS | Major League Soccer |
| MMGF | My Mom Going Far |
| MMSL | Manitoba Major Soccer League |
| MMSL | Middlesex Masters Soccer League |
| MNSA | Marple Newtown Soccer Association |
| MNST | Mexican National Soccer Team |
| MOSC | Mount Olive Soccer Club |
| MOSL | Maryland Open Soccer League |
| MRS | Mount Royal Soccer |
| MRSC | Mike Rose Soccer Complex |