1. any of numerous orchids of the genus Pterostylis having leaves in a basal rosette and green flowers often striped purple or brown or red with the dorsal sepal incurved to form a hood • Syn: greenhood • Hypernyms: orchid, orchidaceous plant • Member Holonyms: Pterostylis, genus Pterostylis 2. any of several orchids of the genus Coryanthes having racemes of a few musky-scented waxy flowers with a helmet-shaped lip process • Syn: helmetflower • Hypernyms: orchid, orchidaceous plant • Member Holonyms: Coryanthes, genus Coryanthes