mistletoe, common name for the Loranthaceae, a family of chiefly tropical hemiparasitic herbs and shrubs with leathery evergreen leaves and waxy white berries. They have green leaves, but they manufacture only part of the nutrients they require. Mistletoes are aerial hemiparasites, attaching themselves to their hosts by modified roots called haustoria, with which they absorb water and food from the host. The list of hosts is varied and numerous.
Mistletoes are widely used for Christmas decoration. The custom of kissing under a branch of mistletoe apparently originated among the Druids and other early Europeans, to whom mistletoe was sacred. From early times it has been associated with folklore and superstition; it was thought to cure many ills.
The mistletoe most widely sold in America is Phoradendron flavescens; most popular in Europe is the "true" mistletoe, Viscum album of the related family Viscacceae, which is parasitic especially on apple trees. An American genus ( Arceuthobium ) with several species found along the Pacific coast is parasitic on conifers. The largest genus of the family, Loranthus, is predominantly African.
The mistletoe family is classified in the division Magnoliophyta, class Magnoliopsida, order Santalales.