| Abbreviation | Definition |
|---|---|
| M&RO | Maintenance and Refurbishment Operations |
| M/F | Maintenance Factor |
| M/I | Minimum Impulse |
| M/L | Maintenance Loop |
| M/LR | Maintenance Loop Recorder |
| M/P | Main Parachute |
| M/R | Mixture Ratio of fuel to oxidizer |
| M/R | Mixture Ratio (Fuel to Oxidizer) |
| M/R | Mixture Ratio of fuel to oxidizer |
| M/S | Measurement Stimuli |
| M/SCI | Mission/Safety Critical Item |
| M/U | Mockup |
| M+R | Maintenance and Refurbishment |
| M+R | Maintenance and Repair |
| M50 | Mean of 1950 Coordinate System |
| MA | MAintenance |
| MA | Maintenance Ability |
| MA | Martin Ablator |
| MA | Master |
| MA | Master Alarm |