any of a genus of shrubs and trees of the heather family with that have clusters of showy red, pink, purple, or white flowers and usu large leathery evergreen leaves: genus Rhododendron
We had passed between the white posts of a gate and up a curving drive, lined with rhododendron bushes — Conan Doyle
[from the Latin genus name, from Greek rhododendron rosebay, from rhodon rose + dendron tree]