American Heritage Dictionary
(5)
Century Dictionary
(5)
GNU Webster's 1913
(1)
WordNet
(2)
Elsewhere on the web
During the week, the atrium is available for parties of 30-50.— St. Louis Business News - Local St. Louis News | The St. Louis Business Journal
Springfield Gardens resident Al Willton, 38, said he thought the atrium was a dangerous feature.
In keeping with its sense of modern living, the centrepiece of the atrium will be a DJ booth overlooking the lobby with a resident DJ setting the mood of the hotel with stylish mixes.— ASIA Travel Tips.com
The buildings surrounding the atrium are also the location of the Canyon Ranch Spa Club and the hotel's fitness center.— MousePlanet

American Heritage Dictionary (1)
Century Dictionary (1)
Bubble size: how much this word was used in a year
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You can expect to see this word about once a month.