| Abbreviation | Definition |
|---|---|
| MSSS | Multiple Sclerosis Service Society |
| MSTF | Marine Science and Technology Foundation |
| MSV | Men Stopping Violence |
| MSVW | Main Street Van Wert |
| MSWA | Maharashtra Societies Welfare Association |
| MSWA | Multiple Sclerosis Society of Western Australia |
| MT | Membership Training |
| MTAI | Music-Thanatology Association International |
| MTAM | Massage Therapy Association of Manitoba |
| MTC | Mission To Children |
| MTCE | Metta Trust for Childrens Education |
| MTF | Michigan Turfgrass Foundation |
| MTF | Montecito Trails Foundation |
| MTF | Musculoskeletal Transplant Foundation |
| MTFK | Mother Teresa Foundation; 'Kerala' |
| MTFR | MounTain FoRum |
| MTFW | Masonry Technology Foundation of Wisconsin |
| MTIAPI | Medical Transcription Industry Association of the Philippines, Inc. |
| MTM | Missions to Military, Inc. |
| MTMI | Mission To Military, Inc. |