brain coral vs stony coral

brain coral and stony coral both are nouns.

Word	Noun	Adjective	Verb	Adverb
brain coral	Yes	No	No	No
stony coral	Yes	No	No	No

As nouns, stony coral is a hypernym of brain coral; that is, stony coral is a word with a broader meaning than brain coral:

brain coral: massive reef-building coral having a convoluted and furrowed surface
stony coral: corals having calcareous skeletons aggregations of which form reefs and islands

Other hypernyms of brain coral include madrepore, madriporian coral.

brain coral (noun)	stony coral (noun)
massive reef-building coral having a convoluted and furrowed surface	corals having calcareous skeletons aggregations of which form reefs and islands