- Massi, Francesca1
- Mathematics, Jewish1
- Mathematics, Medieval1
- Mattei, Teo1
- Matteo, Bernardo di1
- Matteo, Giovanni di1
- Maurice, Saint, -approximately 2871
- Maximian, Emperor of Rome, approximately 240-3101
- Maḥbūbī, Maḥmūd ibn ʻUbayd Allāh, -1344 or 1345. Wiqāyat al-riwāyah fī masāʼil al-Hidāyah1
- Maḥbūbī, ʻUbayd Allāh ibn Masʻūd, -1346 or 1347. Wishāḥ fī al-maʻānī wa-al-bayān1
- Mecco, Francesca di1
- Mecco, Xalento di1
- Medical astrology1
- Medici, Alamanno de'1
- Medici, Bernardo de'1
- Medici, Giovenco de'1
- Medici, Giuliano de'1
- Medici, Niccolò de'1
- Medici, Vanne de'1
- Medicinal plants1