Synonyms for Rock Brake (same or very similar meaning)
WordNet sense 1 (any of several small lithophytic ferns of tropical and warm temperate regions):
cliff brake, cliff-brake
WordNet sense 2 (chiefly lithophytic or epiphytic fern of North America and east Asia):
rock polypody, American wall fern, Polypodium virgianum
From the ODE community, based on WordNet
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