any evergreen or deciduous shrub or tree belonging to the genus Rhododendron, of the heath family, having rounded clusters of showy, pink, purple, or white flowers and oval or oblong leaves.
Origin: 1595–1605; < L < Gk rhodódendron (rhódo-rhodo-+ déndron tree)
rho·do·den·dron (rō'də-děn'drən) n. Any of numerous usually evergreen ornamental shrubs of the genus Rhododendron of the North Temperate Zone, having clusters of variously colored, often bell-shaped flowers.
[Latin, oleander, from Greek : rhodo-, rhodo- + dendron, tree; see deru- in Indo-European roots.]