class Dicotyledonae vs dicot family

class Dicotyledonae and dicot family both are nouns.

Word	Noun	Adjective	Verb	Adverb
class Dicotyledonae	Yes	No	No	No
dicot family	Yes	No	No	No

class Dicotyledonae (noun)	dicot family (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	family of flowering plants having two cotyledons (embryonic leaves) in the seed which usually appear at germination