Definition of Mistletoe at Dictionary.com

a Eurasian evergreen shrub, Viscum album, with leathery leaves, yellowish flowers, and waxy white berries: grows as a partial parasite on various trees: used as a Christmas decoration: family Viscaceae

any of several similar and related American plants in the families Loranthaceae or Viscaceae, esp Phoradendron flavescens

mistletoe cactus an epiphytic cactus, Rhipsalis cassytha, that grows in tropical America