rose window

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 term 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 name 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

wikipedia

North Rose window – Notre Dame Cathedral about 1250