T4 or T-4 may refer to:
Airports and airlines Heathrow Terminal 4 Tiyas Military Airbase, also known as the T-4 Airbase
Biology and medicine T4 phage, a bacteriophage Thyroxine (T4), a form of thyroid hormone T4 or thoracic spinal nerve 4 the fourth thoracic vertebrae of the vertebral column A non-small cell lung carcinoma staging for a type of tumour A CD4 + T lymphocyte T4: an EEG electrode site according to the 10-20 system T4, a tumor class in the TNM staging system
Entertainment T4 (Channel 4), the former daytime teen-aimed slot on Channel 4 in the UK Terminator Salvation, sometimes referred to as Terminator 4 Transformers: Age of Extinction, the fourth film in the live-action Transformers film series
Software and video games Text Template Transformation Toolkit, a technology developed by Microsoft Tekken 4, a 2001 fighting game
Rail transport T4 Eastern Suburbs & Illawarra Line, a Sydney Trains railway service, Australia Île-de-France tramway Line 4 T4 (Istanbul Tram) Cleveland line (numbered T4), a Queensland Rail service, Australia Shorncliffe line (numbered T4), a Queensland Rail service, Australia
Vehicles Dayton-Wright T-4, a 1918 American light, single-seat reconnaissance aircraft Kawasaki T-4, a Japanese aircraft Soyuz T-4, a space mission Sukhoi T-4, a Soviet aircraft Tatra T4, a 1967 Czechoslovak tram Thaden T-4, a 1930s American four-seat all-metal cabin monoplane Troller T4, a Brazilian off-road vehicle Volkswagen Transporter series IV van a model of the OS T1000 train of the Oslo Metro Model T4 Cunningham experimental armored car, later the M1 Armored car
Weapons and explosives T-4 Atomic Demolition Munition, a small tactical nuclear bomb G7e/T4, a Falke German torpedo The Italian name for the high explosive RDX
Other uses Great East Road, a road in Zambia T4 road (Tanzania), a road in Tanzania Lockheed Martin's High beta fusion reactor prototype, called T4 A T4 slip, a tax return form used in income taxes in Canada Aktion T4, Nazi Germany's mass-murder of the mentally and physically disabled Normal space in topology Version 4 of Traveller role-playing game T4, one of several fluorescent-lamp formats A tornado intensity rating on the TORRO scale SPARC T4, a microprocessor introduced by Oracle Microelectronics in 2011
See also The Four T's (disambiguation) 4T (disambiguation) TTTT Type 4 (disambiguation)