class Trematoda vs parasitic worm

class Trematoda and parasitic worm both are nouns.

Word	Noun	Adjective	Verb	Adverb
class Trematoda	Yes	No	No	No
parasitic worm	Yes	No	No	No

class Trematoda (noun)	parasitic worm (noun)
parasitic flatworms (including flukes)	worm that is parasitic on the intestines of vertebrates especially roundworms and tapeworms and flukes