noun, plural a·tri·a [ey-tree-uh] /ˈeɪ tri ə/, a·tri·ums.
- Also called cavaedium. the main or central room of an ancient Roman house, open to the sky at the center and usually having a pool for the collection of rain water.
- a courtyard, flanked or surrounded by porticoes, in front of an early or medieval Christian church.
- a skylit central court in a contemporary building or house.
Origin of atrium
Related formsa·tri·al, adjectivein·ter·a·tri·al, adjective
Examples from the Web for atrial
The two atrial tubes of each zooid remain separate in front but unite posteriorly.
The oral opening into the branchial sack is directed upwards: an atrial opening is remarkably enough not present.
From the atrial chamber the water flows out into the external world.A Guide to the Study of Fishes, Volume 1 (of 2)|David Starr Jordan
During the above described processes the test remains quite intact, and is not perforated at the oral or the atrial openings.
It contains the whole of the nervous system (ng), which is covered behind by the opening of the atrial tubes (cl).