Definition:

diaphragmlisten (DY-uh-fram)

The thin muscle below the lungs and heart that separates the chest from the abdomen.

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Respiratory anatomy; drawing shows right lung with upper, middle, and lower lobes; left lung with upper and lower lobes; and the trachea, bronchi, lymph nodes, and diaphragm. Inset shows bronchioles, alveoli, artery, and vein.