| Abbreviation | Definition |
|---|---|
| MBFC | Mount Barker Football Club |
| MBPC | Mercer Bucks Pickleball Club |
| MBRC | Miami Beach Rowing Club |
| MBSC | Midshipman Black Studies Club |
| MBSC | Midshipmen Black Studies Club |
| MBSC | Monterey Bay Swim Club |
| MBTC | Melbourne Bicycle Touring Club |
| MBTC | Metropolitan Bilingual Toastmasters Club |
| MBTC | Myrtle Beach Tri Club |
| MBTC | Myrtle Beach Triathlon Club |
| MBWC | Minneapolis Boxing and Wrestling Club |
| MBWC | Mission Beach Women's Club |
| MBWC | Moray Business Women Club |
| MBWC | Myrtle Beach Womans Club |
| MBWC | Myrtle Beach Woman's Club |
| MBYC | Macassa Bay Yacht Club |
| MBYC | Manhasset Bay Yacht Club |
| MBYC | Maple Bay Yacht Club |
| MBYC | Marina Bay Yacht Club |
| MBYC | Meydenbauer Bay Yacht Club |