ˈkad.ə(r)ˌfȯil, ˈka.trəˌf- noun
Etymology: Middle English quaterfoil set of four leaves, from Middle French quatre four + Middle English -foil (as in trefoil )
1. : a conventionalized representation of a flower with four petals or of a leaf with four leaflets
an allover pattern of tiny emerald green quatrefoils — Parke-Bernet Galleries Catalog
specifically : a heraldic representation of a flower with four petals
2. : a figure enclosed by four joined foils ; specifically : a 4-lobed foliation in Gothic tracery
• qua·tre·foiled -ld adjective