cliff-brake vs rock brake

cliff-brake and rock brake both are nouns.

Word	Noun	Adjective	Verb	Adverb
cliff-brake	Yes	No	No	No
rock brake	Yes	No	No	No

As nouns, cliff-brake and rock brake are synonyms defined as:

cliff-brake and rock brake: any of several small lithophytic ferns of tropical and warm temperate regions

Other synonyms of cliff-brake include cliff brake.

cliff-brake (noun)	rock brake (noun)
any of several small lithophytic ferns of tropical and warm temperate regions	chiefly lithophytic or epiphytic fern of North America and east Asia
	dwarf deciduous lithophytic ferns
	any of several small lithophytic ferns of tropical and warm temperate regions