A circular window with mullions and tracery, generally radiating from the center, filled with stained glass. It is so named from its fancied resemblance to a rose. It is a beautiful characteristic of Gothic architecture in which it was developed. At first it was placed under a round, then under a pointed arch, where soon it was inscribed in a square with spandrils. Finally in a tier of lower windows it became the center of a vast composition. Roses filled with glass of great beauty were used by the Lombard builders of Italy.