Atrium is defined as a patio, rectangular in shape and open to the elements, attached to a house or is a courtyard, usually located in the center of a building with several floors, and typically has a skylight at the very top.(noun)
The definition of an atrium is a body cavity, specifically relating to the heart’s chambers which take in blood.(noun)
When a person has open-heart surgery to repair a blockage in an artery which gives blood to the heart, it is an example of surgery on their atrium.
See atrium in Webster's New World College Dictionary
See atrium in American Heritage Dictionary 4
noun pl. a·tri·a (āˈtrē-ə) or a·tri·ums
Origin: Latin ātrium; see āter- in Indo-European roots.
Learn more about atrium