| Noun | 1. | genus Epiphyllum - small genus of tropical American (mainly Central America) cacti U.S.A., United States, United States of America, US, USA, America, the States, U.S. - North American republic containing 50 states - 48 conterminous states in North America plus Alaska in northwest North America and the Hawaiian Islands in the Pacific Ocean; achieved independence in 1776 caryophylloid dicot genus - genus of relatively early dicotyledonous plants including mostly flowers epiphyllum, orchid cactus - any cactus of the genus Epiphyllum having flattened jointed irregularly branching stems and showy tubular flowers |