Encyclopedias, Almanacs, Transcripts, and Maps
- Singer, Peter Alfred David (1946 – ) Australian Philosopher and Animal Rights Activist
- Sinhala Religion
- Sinkholes
- Siphonaptera (Fleas)
- Sipuncula (Peanut Worms)
- Sirenia (Dugongs, Sea Cows, and Manatees)
- Sirens and Dwarf Sirens (Sirenidae)
- Sirhindī, Aḥmad
- Site Index
- Skeptics and Skepticism
- Skidding
- Skiing World Cup
- skink
- Skinks (Scincidae)
- skittles
- Skobtsova, Maria
- Sky: Myths and Symbolism
- Sky: The Heavens as Hierophany
- Slash and Burn Agriculture
- Slavic Religion