class Dicotyledones vs class Angiospermae

class Dicotyledones and class Angiospermae both are nouns.

Word	Noun	Adjective	Verb	Adverb
class Dicotyledones	Yes	No	No	No
class Angiospermae	Yes	No	No	No

class Dicotyledones (noun)	class Angiospermae (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	comprising flowering plants that produce seeds enclosed in an ovary; in some systems considered a class (Angiospermae) and in others a division (Magnoliophyta or Anthophyta)