EXAMPLES FROM THE WEB FOR ATRIUM
In the house of Vettius the two money chests were found in the atrium.
This basin was in the center of the atrium, the most important room in the house.
Fauces, the passage from the atrium to the peristyle in a Roman house.
Tablinum, in a Roman house, the room between the atrium and the peristyle.
They left the hall leisurely and found a vacant settle in the atrium.
A man in evening dress came out into the atrium, lighting a cigarette.
Without looking to right or left he strode across the atrium.
The tablinum was an appendage of the atrium, and usually entirely open to it.
From the atrium a narrow fauces or corridor led into the garden.
The nearer doors belong to chambers which open into the atrium.
WORD ORIGIN
1570s, from Latin atrium "central court or main room of an ancient Roman house, room which contains the hearth," sometimes said (on authority of Varro, "De Lingua Latina") to be an Etruscan word, but perhaps from PIE *ater- "fire," on notion of "place where smoke from the hearth escapes" (through a hole in the roof). Anatomical sense of "either of the upper cavities of the heart" first recorded 1870. Meaning "skylit central court in a public building" first attested 1967.