Catherine wheel (window)
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College shield of St. Catharine's College, Cambridge
A Catherine wheel is a spoked circular window. It is named after Saint Catherine of Alexandria who, according to legend, was martyred on a spiked wheel, called a breaking wheel. The wheel is prominently depicted on the St. Catharine's College shield. It is also called a spike wheel. She (Catherine) was supposedly martyred for refusing to marry a man she did not love.