Encyclopedias, Almanacs, Transcripts, and Maps
- Transantarctic Mountains
- Transbaykalia
- Transcarpathian Region
- Transcaspian Region
- transcendental number
- transdermal delivery system
- transdermal patch
- transfinite number
- transit compass
- Transleithania
- Transoxiana
- Transpadane Republic
- Transportation, United States Department of
- Tranströmer, Tomas
- Transylvania Company
- Transylvanian Alps
- trapdoor spider
- Trapezus
- traprock
- trapshooting