Encyclopedias, Almanacs, Transcripts, and Maps
- Mbona
- McCartney, Sir Paul
- McCullin, Donald
- McHarg, Ian Lennox (1920 – 2001) Scottish Design Ecologist and Writer
- McKibben, Bill Ernest (1960 – ) American Environmentalist and Writer
- Measurement and Sensing
- mechanical advantage
- Mechanical Transmission of Energy
- Mecoptera (Scorpionflies and Hangingflies)
- Media and Religion
- Medical Ethics
- medieval music
- Mediterranean Fruit Fly
- Meegeren, Hans van
- megabyte
- Megalithic Religion
- Megalithic Religion: Historical Cultures
- Megalithic Religion: Prehistoric Evidence
- Megaloptera (Dobsonflies, Fishflies, and Alderflies)
- Megawatt (MW)