any gymnosperm plant of the phylum Genetophyta, which includes three genera: Gnetum, consisting of small tropical trees and vines, Ephedra (see ephedra), and Welwitschia (see welwitschia)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Any of a small but diverse phylum (Gnetophyta) of gymnosperm plants with some features similar to those of angiosperms, such as xylem with vessels, strobili resembling inflorescences, and the absence of archegonia. The genus Ephedra, well-known as a source of stimulant compounds, is classified among the gnetophytes.
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