| MAS |
Meteorological Aids Service |
| MAT |
Mobile Aeronautical Telemetry |
| MBS |
Mobile Broadband System |
| MC |
Monte Carlo (methodology) |
| MDS |
Multipoint Distribution Service |
| MEO |
Medium Earth Orbit (satellite) |
| MERLIN |
Multi-Element Radio Linked INterferometer (GB) |
| MES |
Mobile Earth Station |
| MESA |
Mobility for Emergency and Safety Applications |
| MetA |
Meteorological Aid Service |
| METSAT |
Meteorological Satellite |
| MetS |
Meteorological-Satellite Service |
| MF |
Medium Frequency (300 to 3000 kHz) |
| MIDS |
Multifunctional Information Distribution System |
| MIFR |
Master International Frequency Register |
| MIT |
Massachusetts Institute of Technology (USA) |
| ML |
Mobile station (in a mobile radio system) |
| MLS |
Microwave Landing System |
| MLS |
Microwave Limb Sounding |
| MM |
Maritime Mobile Service |
| MMARC |
Maritime Mobile Radio Conference |
| MMDS |
Multimedia Multipoint Distribution System |
| MMS |
Maritime Mobile Service |
| MMSS |
Maritime Mobile-Satellite Service |
| MNP |
Mobile Number Portability |
| MOB |
Mobile (use in the designation of certain WARCs) |
| MoU |
Memorandum of Understanding |
| MRC |
Milestone Review Commitee (CEPT) |
| MRN |
Maritime Radionavigation Service |
| MRNS |
Maritime Radionavigation Service |
| MRNSS |
Maritime Radionavigation-Satellite Service |
| MS |
Mobile Service |
| MS |
Mobile Station |
| MSA |
Meteor Scatter Applications |
| MSS |
Mobile Satellite Service |
| MVDS |
Multipoint Video Distribution System |
| MWS |
Multimedia Wireless Systems |
Committee on Radio Astronomy Frequencies