Rose window is often used as a generic term applied to a circular window, but is especially used for those found in churches of the Gothic architectural style that are divided into segments by stone mullions and tracery. The name “rose window” was not used before the 17th century and according to the Oxford English Dictionary, among other authorities, comes from the English flower name rose.
The term “wheel window” is often applied to a window divided by simple spokes radiating from a central boss or opening, while the term “rose window” is reserved for those windows, sometimes of a highly complex design, which can be seen to bear similarity to a multi-petalled rose. Rose windows are also called Catherine windows after Saint Catherine of Alexandria who was sentenced to be executed on a spiked wheel. A circular window without tracery such as are found in many Italian churches, is referred to as an ocular window or oculus.
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