Vitruvian opening
Window or frame that widens from top to bottom From Wikipedia, the free encyclopedia
A Vitruvian opening is a window or frame that is slightly larger at the bottom than the top.
The term was first described by Vitruvius and mentioned by Andrea Palladio, referring to a window at the Temple of Vesta at Tivoli. The term Tivoli window is also used.[1]
References
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