Illustrated Architecture Dictionary
Foil
Pronounced: FOYL
A lobe or leaf-shaped curve formed between cusps inside an arch or circleIn French, "foil" means "leaf"
The number of foils is indicated by a prefix, e.g. trefoil, quatrefoil, cinquefoil, sexfoil, multifoil
Mouchette: A daggerlike motif found especially in 14th cent. Gothic tracery, formed by elliptical and ogee curves so that it is pointed at one end and circular at the other.
Foils found in Gothic and Gothic Revival styles
See also: Vocabulary - Churches
Examples from Buffalo architecture