t12

T12 may refer to several distinct topics. In anatomy, T12 denotes the twelfth thoracic vertebra of the human spine. It is part of the thoracic region, located between T11 and L1, and it articulates with the 12th rib. The T12 vertebra helps stabilize the thoracic cage and supports the transition to the lumbar spine; it possesses typical thoracic features such as a heart-shaped body and a relatively long spinous process. Injuries such as compression fractures can affect the T12 level, and it is a common landmark in imaging and spine surgery planning.

In neurology, T12 can refer to the thoracic spinal nerve labeled T12. The T12 nerve exits below the T12 vertebra and contributes to the subcostal nerve, providing motor and sensory fibers to the abdominal wall and back.

In lighting technology, T12 denotes a fluorescent lamp with a diameter of 12/8 inch (1.5 inches). T12 lamps were common in older fixtures and require appropriate ballasts and fixtures. Modern substitutes include T8 and T5 lamps, which offer higher efficiency in many installations.

Other uses of T12 exist in product naming and standards, where it serves as a model, designation, or version code. The intended meaning is determined by context.