Synonyms for Greenbrier (same or very similar meaning)
WordNet sense 1 (a very prickly woody vine of the eastern United States growing in tangled masses having tough round stems with shiny leathery leaves and small greenish flowers followed by clusters of inedible shiny black berries):
briar, brier, bullbrier, catbrier, horse-brier, Smilax rotundifolia
From the ODE community, based on WordNet
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