Having the leaves of a pentamerous calyx or corolla so imbricated that two are exterior, two are interior, and the other has one edge exterior and one interior; as, quincuncial aestivation.
QUINCUNCIAL
Meaning of QUINCUNCIAL in English
Webster's Revised Unabridged English Dictionary. Пересмотренный полный словарь английского языка Webster. 2012