Encyclopedias, Almanacs, Transcripts, and Maps
- Guyot de Provins
- Guyots and Atolls
- Guzyk, Jan (1875-1928)
- Gymnures and Hedgehogs: Erinaceidae
- Gyromancy
- H5N1
- Ha-Levi, Judah ben Samuel (ca. 1085-ca. 1140)
- Haas, George C(hristian) O(tto) (1883-1964)
- Habondia (or Habundia)
- Hacker Ethics
- Hades Base
- Hadron, Heavy
- Hag of the Dribble
- Hagfishes: Myxini
- Haigneré, Claudie
- Haim-Munk Syndrome
- Haines, Frederick H(enry) (1869-1944)
- Hair Loss Syndromes
- Hair Worms: Nematomorpha
- Hajoth Hakados