Encyclopedias, Almanacs, Transcripts, and Maps
- Mousebirds: Coliiformes
- Moustached Bats: Mormoopidae
- Moyamoya
- Moyamoya
- Moyamoya Disease
- Moyes, Winifred (d. 1957)
- Mt. Ararat
- Mucolipidosis
- Mucopolysaccharidosis Type I
- Mucopolysaccharidosis Type II
- Mud Flow
- Mudnest Builders: Grallinidae
- Mueller III, Robert S
- Muhammed ibn Ahmad al-Maqdisi
- Muhyi l'din al-Maghribi
- Muir-Torre Syndrome
- Muktananda, Swami (1908-1982)
- Mulberry Family (Moraceae)
- Mulberry Family (Moraceae)
- Mulchuyse, S