thoracotomy

n. incision into the chest (Medicine)

Thoracotomy is an incision into the chest. It is performed by a surgeon, and, rarely, by emergency physicians and paramedics, to gain access to the thoracic organs, most commonly the heart, the lungs, the esophagus or thoracic aorta, or for access to the anterior spine such as is necessary for access to tumors in the spine.
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Thoracotomy /tho·ra·cot·o·my/ pleurotomy; incision of the chest wall. tho·ra·cot·o·my n. Incision into the chest wall. Also called pleurotomy. [more]Thoracotomy - Community and Resources

(n.)
The operation of opening the pleural cavity by incision.
  

An operation to open the chest.