A quatrefoil is an ornamental shape with four lobes, common to Gothic architectural or sculptural decoration. In the Renaissance, the quatrefoil design persisted in some regions until the 15th century. In Venice, the Doge's Palace (1340-1438) includes them as ornamentation in its upper arcade, while in Florence the quatrefoil appears on the east doors (1403-1424) of the Baptistery, used by Lorenzo Ghiberti as the background fields for his biblical scenes.
Historical dictionary of Renaissance art. Lilian H. Zirpolo. 2008.