atrium
noun
[ ˈeɪtrɪəm ]
• an open-roofed entrance hall or central court in an ancient Roman house.
• each of the two upper cavities of the heart from which blood is passed to the ventricles. The right atrium receives deoxygenated blood from the veins of the body, the left atrium oxygenated blood from the pulmonary vein.
Origin:
late 16th century: from Latin.
