T4

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
 * the T4 spinal nerve
 * 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

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

 * Eastern Suburbs & Illawarra Line, a Sydney Trains railway service
 * Île-de-France tramway Line 4
 * T4 (Istanbul Tram)

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 Czechoslovakian tram
 * Thaden T-4, a 1930s American four-seat all-metal cabin monoplane
 * 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