- Massachusetts--Williamstown2
- Maurice, Saint, -approximately 2871
- Małogoszcz (Poland)1
- Medea, consort of Aegeus, King of Athens (Mythological character)1
- Medicinal plants1
- Medicine2
- Medicine, Magic, mystic, and spagiric1
- Medicine--Formulae, receipts, prescriptions1
- Meditations6
- Mehmed II, Sultan of the Turks, 1432-14811
- Melanchthon, Philip, 1497-1560. De officio principum1
- Mensural notation11
- Metal clasps1
- Metaphysics1
- Mexico4
- Mexico--Chiapas1
- Mexico--Mexico City1
- Mexico--Michoacán de Ocampo1
- Michael (Archangel)1
- Michaelmas1