• WordNet 3.6
    • n atrium the central area in a building; open to the sky
    • n atrium any chamber that is connected to other chambers or passageways (especially one of the two upper chambers of the heart)
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Webster's Revised Unabridged Dictionary
    • Atrium (Zoöl) A cavity in ascidians into which the intestine and generative ducts open, and which also receives the water from the gills. See Ascidioidea.
    • Atrium (Anat) A cavity, entrance, or passage; as, the atrium, or atrial cavity, in the body wall of the amphioxus; an atrium of the infundibula of the lungs, etc.
    • Atrium (Arch) A square hall lighted from above, into which rooms open at one or more levels.
    • Atrium (Arch) An open court with a porch or gallery around three or more sides; especially at the entrance of a basilica or other church. The name was extended in the Middle Ages to the open churchyard or cemetery.
    • Atrium (Anat) The main part of either auricle of the heart as distinct from the auricular appendix. Also, the whole articular portion of the heart.
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Century Dictionary and Cyclopedia
    • n atrium In anc. Rom. arch., the entrance-hall, the most important and usually the most splendid apartment of the house. At an early period, and later among the poor, the atrium was used not only as a ceremonial room, but as a reception-room and for general domestic purposes, as cooking and dining. In it were placed the ancestral images and heirlooms, the marriage-couch, the focus or hearth, and generally a small altar. Later, among the wealthy, and when separate apartments were built for kitchen and dining-room, chapel of the lares, etc., it was reserved as a general reception- and show-room. It was lighted by an opening in the roof, called the compluvium, toward which the roof sloped, so as to conduct the rainwater into a cistern in the floor, called the impluvium.
    • n atrium A hall or court resembling in arrangement an atrium proper, as at the entrance of some classical or early Christian public buildings, etc.
    • n atrium [NL.] In anatomy, an auricle of the heart, or some equivalent venous cardiac cavity.
    • n atrium [NL.] In zoology: The chamber or cavity of ascidians, communicating with the exterior, and with the cavity of the alimentary canal. See atrial, and cut under Tunicata.
    • n atrium A membranous saccular diverticulum of the ear in fishes: as, the atrium sinus imparis, a membranous sac given off from the sinus auditorius impar of fishes, and connected in various ways with the air-bladder.
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Chambers's Twentieth Century Dictionary
    • n Atrium ā′tri-um the entrance-hall or chief apartment of a Roman house.
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Webster's Revised Unabridged Dictionary
L., the fore court of a Roman house
Chambers's Twentieth Century Dictionary
Prob. orig. the kitchen, and so lit. 'the apartment blackened with smoke'—L. ater, black; others connect the word with ædes, orig. a fireplace, then a house, a temple.


In literature:

The northern wall of the atrium is original, as the crosses in brick formed in its brickwork show.
"Byzantine Churches in Constantinople" by Alexander Van Millingen
The scene is a brilliant atrium, surrounded by majestic pillars.
"Six Centuries of Painting" by Randall Davies
Perhaps they hoped to salvage the strong box in the atrium, or a heirloom from the triclinium.
"Cooking and Dining in Imperial Rome" by Apicius
"Architecture" by Thomas Roger Smith
From the Coliseum's vast area to that of the smallest atrium in the Pompeian house, the covering principle was the same.
"Needlework As Art" by Marian Alford
The lions from the ancient cathedral doors are now in the atrium of the high-school.
"The Shores of the Adriatic" by F. Hamilton Jackson
Tomb of Dogaressa Vital Michele, in St. Mark's atrium.
"The Stones of Venice, Volume III (of 3)" by John Ruskin
In the centre of the atrium was the impluvium, a rectangular marble tank to catch and hold the waters from the roof.
"Sónnica" by Vicente Blasco Ibáñez
We will meet in Carinus's atrium to-morrow.
"A Christian But a Roman" by Mór Jókai
Licinius rushed impetuously before the others through the well-known vestibule and the colonnade of the atrium to the study of Cethegus.
"A Struggle for Rome, v. 1" by Felix Dahn

In news:

The Books Are Fun Book Fair will be held from 7 am to 4 pm Nov 26, 27 and 28 in the Atrium of the Robinson Medical Arts Building, 6847 N Chestnut St, Ravenna.
A giant double-helix scultpure hangs in the atrium of the Bond Life Sciences Center on the University of Missouri campus.
The atrium of the B.C.
Parents-to-be can get useful information and tour the Birthing Center at Western Baptist Hospital's annual free Childbirth Fair from 10 am to noon Saturday in the atrium of Doctor's Office Building 2.
Curly 's Pub in the Lambeau Field Atrium had a grand re-opening bash today with the first one-hundred tables getting a free order of cheese curds.
A culinary demonstration at 2 pm Sunday, Dec 16, at Vitality Nutrition LLC at the Atrium of Novi, 43155 Main St, Suite 305B-1.
The morning after winning the governor's seat, Chris Christie met with nine staffers and consultants in the atrium of the Hilton Hotel here to discuss his transition and activities throughout the day and tomorrow.
Innovation Partnership Building Atrium.
The first view for visitors to the Ralph L Carr Judicial Center will be of the building's glass-domed, 100-foot-high atrium.
The Center Café is finding a new home in the Center Ithaca Atrium.
Metropolitan Realty Associates has refinanced Jericho Atrium, its 147,183-square-foot, two-story office building in Jericho , with an $18.5 million loan from Capital One Bank, according to a company statement.
Its black glass exterior soars high above Fifth Avenue, and its gold-tipped revolving doors have spun the likes of Bruce Willis and Anne Hathaway into its waterfall-splashed atrium.
Leap into 2013 at Lambeau Field will be held on New Year's Eve in the Lambeau Field Atrium.
A giant double-helix scultpure hangs in the atrium of the Bond Life Science s Center on the University of Missouri campus.
An artist's rendering of the interior of an atrium equipped with the solar-shading modules.

In science:

Heart activity is driven by periodic signals emitted by the cells of the sinus node situated in the upper right atrium.
Spiral Turbulence: From the Oxidation of CO on Pt(110) to Ventricular Fibrillation