Any member of several genera of orchids in which the lip of the flower is slipper-shaped. The genus Cypripedium has about 50 temperate and subtropical species. Two well-known species, the yellow lady's slipper (C. calceolus) and the pink lady's slipper, or moccasin flower (C. acaule), are found in temperate coniferous woods in early spring. Other genera include Phragmipedium and Selenipedium of the New World tropics, and the tropical Asian Paphiopedilum. Many hybrids have been developed.