class Dicotyledonae vs dicot

class Dicotyledonae and dicot both are nouns.

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

class Dicotyledonae (noun)	dicot (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	flowering plant with two cotyledons; the stem grows by deposit on its outside