A very large room, often with glass walls or roof, especially in the middle of a large shop or office building. (Cambridge Dictionary)
An atrium is a part of a building such as a hotel or shopping centre, which extends up through several floors of the building and often has a glass roof. (Collins Dictionary)
The central room of a Roman house. (Merriam – Webster)
An open-roofed entrance hall or central court in an ancient Roman house. (Oxford Dictionaries)
Examples
Atrium. Wiktionary.
Atrium in Architecture: Definition & Overview.
https://study.com/academy/lesson/atrium-in-architecture-definition-lesson-quiz.html
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