has part has part has_part characteristic of has modifier abnormal thoracic cavity morphology small thoracic cavity reduced thoracic cavity size MPheno.ontology MP:0004734 reduced size of the cavity in the vertebrate body enclosed by the ribcage between the diaphragm and the neck, and contains the lungs, heart, thoracic aorta, pulmonary artery and its branches, thymus gland, and the respiratory airway decreased thoracic cavity size abnormal decreased size thoracic cavity