| Abbreviation | Definition |
|---|---|
| MAM | Mile A Minute |
| MAMA2B | Maternal Anthropometry Measurement Apparatus Version 2B (pregnant crash test dummy) |
| MAP | Military Airport Plan |
| MAP | Missed Approach Point |
| MAPS | Military Aviation Preservation Society |
| MAPT | Maine Association for Pupil Transportation |
| MAPT | Massachusetts Association for Pupil Transportation |
| MAPT | Massachusetts Association of Pupil Transportation |
| MAPT | Michigan Association for Pupil Transportation |
| MAPT | Missouri Association for Pupil Transportation |
| MAR | Managed Arrival Reservoir |
| MAR | Minimally Attended Radar |
| MARC | Maryland Area Rapid Commuter |
| MARCH | Maintenance Assessment Ratings and Costing of Highways |
| MARDEZ | Maritime Defense Zones |
| MARS | Maintenance And Ramp Safety |
| MARS | Moving Armature Red Signal |
| MARTA | Massachusetts State Association of Regional Transit Authorities |
| MARTA | Metro Atlanta Rapid Transportation Authority |
| MARTA | Metropolitan Atlanta Rapid Transit Authority |