Synonyms for Medusa's Head (same or very similar meaning)
WordNet sense 1 (African dwarf succulent perennial shrub with numerous slender drooping branches):
Euphorbia caput-medusae, Euphorbia medusae
WordNet sense 2 (weedy rye grass having long bristling awns):
Elymus caput-medusae
From the ODE community, based on WordNet
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