rock brake
noun
any of various ferns of the genera Pellaea and Cryptogramma, which grow on rocky ground and have sori at the ends of the veins
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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Examples from the Web for rock brake
Historical Examples of rock brake
On the same cliff were tufts of the alpine woodsia and dense patches of rock-brake—but these stand in no need of the bee.
In the OpenStanton Davis Kirkham