Any of various gymnospermous, mostly shrubby plants of the genus Ephedra, some of which are used as a source of ephedrine.
A stimulant, often sold as pills or tablets, derived from a plant of this genus.
[Latin ephedra, horsetail, from Greek ephedrā, from feminine of ephedros, sitting upon : ep-, epi-, epi- + hedrā, seat; see sed- in Indo-European roots.]
1917, from Mod.L., coined by Linnæus (1737) from Gk. ephedra, lit. "sitting upon," from fem. of ephedros, from epi "on" + hedra "seat, base, chair, face of a geometric solid," from PIE base *sed- "to sit" (see sedentary).
Main Entry: ephed·ra Pronunciation: i-'fed-r&, 'ef-&d-r& Function: noun 1capitalized: a large genus of jointed nearlyleafless desert shrubs (family Gnetaceae) that have the leaves reduced to scales at the nodes and include some (especially E. sinica) that are a source of ephedrine —see MA HUANG 2: any plant of the genus Ephedra