Encyclopedias, Almanacs, Transcripts, and Maps
- Trogoniformes (Trogons)
- Tropicbirds (Phaethontidae)
- Trubetskoi, Evgenii
- Trubetskoi, Sergei
- True Energy Costs
- True Frogs (Ranidae)
- True Levellers
- True Seals (Phocidae)
- True Toads, Harlequin Frogs, and Relatives (Bufonidae)
- Trueman, Fred
- Trumpeters (Psophiidae)
- Tsaddiq
- tsars of Russia
- Tsong kha pa
- Tsunamis
- Tswana Religion
- Tubulidentata (Aardvarks)
- Tucci, Giuseppe
- Tuco-Tucos (Ctenomyidae)
- Tudors