- Mary, Blessed Virgin, Saint, in the liturgy1
- Mass--Celebration1
- Massachusetts1
- Massachusetts--Northampton1
- Materia medica, Vegetable1
- Mathematics1
- Mathematics, Arab1
- Mathematics, Greek1
- Mathematics, Medieval1
- Medea, consort of Aegeus, King of Athens (Mythological character)1
- Medicinal plants1
- Medicine, Greek and Roman1
- Medicine, Greek and Roman--Manuscripts1
- Medicine, Magic, mystic, and spagiric1
- Mediterranean Region1
- Menorah1
- Merchants1
- Metaphysics1
- Metaphysics (Aristotle)1
- Middle East1