class Dicotyledonae vs magnoliopsid genus

class Dicotyledonae and magnoliopsid genus both are nouns.

Word	Noun	Adjective	Verb	Adverb
class Dicotyledonae	Yes	No	No	No
magnoliopsid genus	Yes	No	No	No

class Dicotyledonae (noun)	magnoliopsid genus (noun)
comprising seed plants that produce an embryo with paired cotyledons and net-veined leaves; divided into six (not always well distinguished) subclasses (or superorders): Magnoliidae and Hamamelidae (considered primitive), Caryophyllidae (an early and distinctive offshoot), and three more or less advanced groups: Dilleniidae, Rosidae, Asteridae	genus of flowering plants having two cotyledons (embryonic leaves) in the seed which usually appear at germination