a depression on both sides of the chest wall of a child between the pectoral muscles and the lower margin of the ribcage. It is caused by exaggerated suction of the diaphragm when breathing in and develops in conditions in which the airways are partially obstructed (e.g. poorly treated asthma) or when the lungs are abnormally congested due to some congenital abnormality of the heart. [E. Harrison (1789–1838), British physician]
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