What is the meaning Thoracic?
It pertains to the thorax... But you can use it as a thoracic spine, thoracic surgery, thoracic cavity, thoracic outlet syndrome, thoracic spine pain, thoracic vertebrae, thoracic medicine, thoracic surgeons, thoracic strains, sprain thoracic, or thoracic spine disorder; it's pretty self explanatory.
There are three parts of the spine, the cervical, thoracic and lumbar. Each vertebrae is listed by its number. For example the first 7 vertebrae (from the top) are listed as C1-C7 meaning C for cervical. The thoracic vertebrae starts after C7, the 8th vertebrae is T1-T12, so there is 12 individual vertebraes in the thoracic spine. After the thoracic, is the lumbar which have 5 individual vertebrae, L1-L5.