class Anthozoa vs anthozoan

class Anthozoa and anthozoan both are nouns.

Word	Noun	Adjective	Verb	Adverb
class Anthozoa	Yes	No	No	No
anthozoan	Yes	No	No	No

class Anthozoa (noun)	anthozoan (noun)
a large class of sedentary marine coelenterates that includes sea anemones and corals; the medusoid phase is entirely suppressed	sessile marine coelenterates including solitary and colonial polyps; the medusoid phase is entirely suppressed