MDN
- East German mark
- List of airline codes (M)
- MDN Web Docs
- MTN (TV station)
- Macedon railway station
- Madison Municipal Airport (Indiana)
- Maiden Newton railway station
- Mbati language
- MdN Interactive
- Medan railway station
- Meriden (Amtrak station)
- Mesoamerican Long Count calendar
- Milwaukee District North Line
- Minggang East railway station
- Ministry of National Defence (Portugal)
- Mobile device number
- Mobile dialable number
- Mobile directory number
- Morden tube station
- Nicaraguan Democratic Movement