Rose window
A rose window is a large circular window filled with stone tracery that radiates from the centre like the petals of a rose or the spokes of a wheel. The form is a hallmark of Gothic architecture and was developed in France in the twelfth century. The finest are set in the end walls of a cathedral transept or above the main entrance, where they fill the wall with coloured light.
Famous examples include those at Chartres Cathedral and Notre-Dame de Paris. In England, Lincoln Cathedral has two large rose windows in its transepts, known as the Dean’s Eye and the Bishop’s Eye. The subjects are often the Last Judgement, the Virgin Mary or the life of Christ, arranged in rings around a central figure.
The term is also used more loosely for any round window with radiating divisions, and by designers for the rose motif in Glasgow Style glass, which is a different thing.