| Abbreviation | Definition |
|---|---|
| MASTIF | Multiple Axis Space Test Inertia Facility |
| MAT | Matrix |
| MAT | Meteorological Atmospheric Turbulence |
| MAT | Multiple Actuator Test |
| MATCO | Materials Analysis, Tracking, and Control |
| MATE | MDM (Manipulator Deployment Mechanism) Application Test Environment |
| MATE | MDM Application Test Environment |
| MAU | Million Accounting Units |
| MAUS | Messenschafteliche Autonome Experiment Unter Schewerelosigkeit |
| MAV | Mars Ascent Vehicle |
| MAXCO | Maximum Dynamic Pressure |
| MB | Main Bus |
| MB | Management Baseline |
| MB | MegaBytes |
| MB | Millibar |
| MBAC | Marshall Booster Assembly Contractor |
| mbar | Millibar |
| MBC | Manual Boost Controller |
| MBC | Maximum Breathing Capacity |
| MBCS | Motion-Base Crew Station |