any member of several genera of orchids, family Orchidaceae, in which the lip of the flower is slipper-shaped. The genus Cypripedium has about 50 temperate and subtropical species. One well-known species is the yellow lady's slipper (Cypripedium calceolus); another is the pink lady's slipper (C. acaule), also known as the moccasin flower. Most species have one or two flowers on a stem about 30 to 60 cm (12 to 24 inches) tall.

About 16 species of lady's slippers constitute the genus Phragmipedium. They are narrow-leaved plants native to tropical America. One to six flowers with ribbonlike petals are borne on a stalk nearly 90 cm tall. The six species in the genus Selenipedium, also native to tropical America, may be 5 m (16 feet) tall. The leaves are folded, and the flowers are borne on a spike at the tip of the plant. Species of Paphiopedilum, a genus of 62 tropical Asian lady's slippers, have mottled or greenish leaves with a leathery texture and large, waxy flowers of various colours. Many hybrids have been developed.