thoracic cavity

space inside the chest, anatomic cavity where the lungs and heart are located

The thoracic cavity (or chest cavity) is the chamber of the human body (and other animal bodies) that is protected by the thoracic wall (thoracic cage and associated skin, muscle, and fascia).
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Thoracic cavity n. The space within the walls of the chest, bounded below by the diaphragm and above by the neck, and containing the heart and the [more]Thoracic cavity - Community and Resources

Noun
1. the cavity in the vertebrate body enclosed by the ribs between the diaphragm and the neck and containing the lungs and heart
(synonym) chest cavity
(hypernym) cavity, bodily cavity, cavum
(part-holonym) thorax, chest, pectus
(part-meronym) mediastinum