What does T3 stand for?

Train-the-Trainer - Army

Triiodothyronine - Also, TITh - Endocrinology

Carrier Facility for DS-3 Formatted Digital Signal Transmission at a Rate 44.746 mbps - Data communications (UWER)

Kiribati - International civil aircraft marking (ODBW)

Solution Heat-Treated, Cold-Worked and Naturally Aged to a Substantially Stable Condition - Temper designation for aluminum alloys (UWER)

Tank Track Test - Army

Terminator 3 - 2003 motion picture

Thyroxin (SAUS)

Transmission link 3 (SAUS)

Transurethral Thermo-Ablation Therapy - Medicine (DAVI)