Wiktionary
octofoil
a. Having eight lobes or leaves. (from 19th c.) n. (context heraldiccharge English) A stylized flower or leaf with eight lobes; a double quatrefoil.
Usage examples of "octofoil".
Above, far back in the clerestory arches, are octofoil windows with sills of over-lapping courses, which incline forward to the string course above the triforium.