- TSI
- TüRkiye Saati Ile (International » Turkish)* Tsimshian (Regional » Language Codes (3 Letters))* Time Slot Interchange (Computing » Telecom)* Transportation Safety Institute (Governmental » US Government)* Transportation Safety Institute (Governmental » Transportation)* Tom Sawyer Island (Regional)* Thyroid Stimulating Immunoglobulin (Medical » Physiology)* Two Speed Idle (Governmental » Transportation)* Turn Signal Intakes (Governmental » Transportation)* Turbo Sport Intercooled (Governmental » Transportation)* TRADOC Simulation Internet (Governmental » Military)* Teachers Summer Institute (Academic & Science » Universities)* Teachers Summer Institute (Community » Educational)* Tsili Tsili, Papua New Guinea (Regional » Airport Codes)* Telecommunication Security Information (Computing » Security)* The Silent Interrogators (Governmental » Military)* Third Season Inconsistency (Community » Sports)
Abbreviations dictionary. 2012.