class Angiospermae vs angiospermous tree

class Angiospermae and angiospermous tree both are nouns.

Word	Noun	Adjective	Verb	Adverb
class Angiospermae	Yes	No	No	No
angiospermous tree	Yes	No	No	No

class Angiospermae (noun)	angiospermous tree (noun)
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)	any tree having seeds and ovules contained in the ovary