many vs legion

many is not a noun while legion is a noun.

Word	Noun	Adjective	Verb	Adverb
many	No	Yes	No	No
legion	Yes	Yes	No	No

many (noun)	legion (noun)
	a vast multitude
	a large military unit
	association of ex-servicemen
	archaic terms for army

many (adjective)	legion (adjective)
a quantifier that can be used with count nouns and is often preceded by `as' or `too' or `so' or `that'; amounting to a large but indefinite number; quantifier, plural pronoun; quantifier, plural	amounting to a large indefinite number