| Acronym | Meaning |
 | MMC | Mid Motor Controller |
 | MMC | Mission Management Center |
 | MMCA | Mid Motor Controller Assembly |
 | MMCA | Midbody Motor Control Assembly |
 | MMCL | Master Measurement And Control List |
 | MMDB | Mass Memory Data Base |
 | MMDB | Master Measurement Data Base |
 | MMDF | Mission Model Data File |
 | MMES | MSFC Mated Element Systems |
 | MMH | Maintenance Man-Hour |
 | MMH | Monomethyl Hydrazine |
 | MMH | Monomethylhydrazine |
 | MML | Master Measurement(s) List |
 | MMLS | Model-Modes-Loads-Stresses |
 | MMOS | Multimode Optical Sensor |
 | MMPSE | Multiuse Mission Payload Support Equipment |
 | MMS | Mission Modular Spacecraft |
 | MMS | Modular Multiband Scanner |
 | MMS | Multimission Modular Spacecraft |
 | MMS | Multimission Modular Spacecraft |
 | MMSE | Multiuse Mission Support Equipment |
 | MMSE | Multiuse Mission Support Equipment |
 | MMT | Mass Memory Test |
 | MMU | Manned Maneuvering Unit |
 | MMU | Manned Maneuvering Unit |
 | MMU | Mass Memory Unit |
 | MMU | Mass Memory Unit |
 | MN | Main |
 | MNA | B |
 | MNVR | Maneuver |
 | MO | Major Objective |
 | MO | Manned Orbiter |
 | MO | Manual Orientation |
 | MO | Manufacturing Order |
 | MO | Master Oscillator |
 | MO | Middeck Overhead |
 | MO | Mission Operations |
 | MO | Molybdenum |
 | MO | Move |
 | MOA | Make On Arrival |
 | MOA | Memorandum Of Agreement |
 | MOA | Minute-of-Angle |
 | MOC | Marine Operation Center |
 | MOC | Mission Operations Computer |
 | MOCF | Mission Operations Computational Facilities |
 | MOCR | Mission Operations Control Room |
 | MOCS | Multichannel Ocean Color Sensor |
 | MOCV | Manual 02 Control Valve |
 | MOD | Modulation |
 | MOD | Module |