thorac(o)-

The chest or thorax.

Greek thōrax, thorāc‑, chest.

A thoracotomy (Greek ‑tomia, cutting) is a surgical incision into the chest wall; the adjective thoracolumbar refers to the thoracic and lumbar regions of the spine; a thoracostomy (Greek stoma, mouth) is an incision made into the chest wall for drainage.