| Abbreviation | Definition |
|---|---|
| MEIT | Multi Element Integration Testing |
| MEIU | Main Engine Interface Unit |
| MEL | Master Equipment List |
| MEL | Modular Electromagnetic Levitator |
| MELEO | Material Exposure in Low Earth Orbit |
| MELI | Master Equipment List Index |
| MELI | Minimum Equipment List Index |
| MELICA | Medium Energy Ion Composition Analyzer |
| MEM | Meteoroid Exposure Module |
| MEM | Module Exchange Mechanism |
| MEMS | MicroElectroMechanical System |
| MEMS | MicroElectroMechanical Systems |
| MEO | Medium Earth Orbit |
| MEOP | Maximum Expected Operating Pressure |
| MEP | Main Engine Propellant |
| MEP | Main Entry Point |
| MEP | Management Engineering Program |
| MEP | Mean Effective Pressure |
| MEP | Minimum Entry Point |
| MEQA&P | Mission, Environmental, Quality Assurance & Policy |