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 rainwater.
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.
Anatomy. either of the two upper chambers on each side of the heart that receive blood from the veins and in turn force it into the ventricles.
- a·tri·al, adjective
- in·ter·a·tri·al, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
How to use atrium in a sentence
Cue atrial fibrillation on my part; I'd already arranged to break my lease, and also, I'd gotten rather fond of him.
In Teleutoscolex there is but one pair of funnels opening into the same segment with the atrial pore.Earthworms and their Allies | Frank E. Beddard
The gills lead also, as in Ascidians, to another cavity, the Atrial chamber.Stories of the Universe: Animal Life | B. Lindsay
The two atrial tubes of each zooid remain separate in front but unite posteriorly.
The atrial cavities in Pyrosoma are clearly lined by epiblast, just as in simple Ascidians.
When the young colony is ready to become free, it escapes from the atrial cavity of the parent, and increases in size by budding.
British Dictionary definitions for atrium
the open main court of a Roman house
a central often glass-roofed hall that extends through several storeys in a building, such as a shopping centre or hotel
a court in front of an early Christian or medieval church, esp one flanked by colonnades
anatomy a cavity or chamber in the body, esp the upper chamber of each half of the heart
- atrial, adjective
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Scientific definitions for atrium
A chamber of the heart that receives blood from the veins and forces it by muscular contraction into a ventricle. Mammals, birds, reptiles, and amphibians have two atria; fish have one.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.