e·phed·ra (ĭ-fĕdrə, ĕfĭ-drə)
1. Any of various usually shrubby gymnosperms of the genus Ephedra, having jointed green stems and small scalelike leaves, some species of which are used as a source of ephedrine.
2. A drug containing ephedrine derived from one of these plants, used in traditional Chinese medicine as a stimulant and decongestant and sold in the United States primarily as a dietary supplement for weight loss before it was banned because of toxic side effects in 2004. Also called ma huang.
[Latin ephedra, horsetail, from Greek ephedrā, from feminine of ephedros, sitting upon : ep-, epi-, epi- + hedrā, seat; see sed- in the Appendix of Indo-European roots.]
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