red coral vs gorgonian

red coral and gorgonian both are nouns.

Word	Noun	Adjective	Verb	Adverb
red coral	Yes	No	No	No
gorgonian	Yes	No	No	No

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

red coral: corals of especially the Mediterranean having pink or red color used for ornaments and jewelry
gorgonian: corals having a horny or calcareous branching skeleton

Other hypernyms of red coral include gorgonian coral.

red coral (noun)	gorgonian (noun)
corals of especially the Mediterranean having pink or red color used for ornaments and jewelry	corals having a horny or calcareous branching skeleton
the hard stony skeleton of a Mediterranean coral that has a delicate red or pink color and is used for jewelry