mediaeval vs Middle Ages

mediaeval is not a noun while Middle Ages is a noun.

Word	Noun	Adjective	Verb	Adverb
mediaeval	No	Yes	No	No
Middle Ages	Yes	No	No	No

mediaeval (noun)	Middle Ages (noun)
	the period of history between classical antiquity and the Italian Renaissance

mediaeval (adjective)	Middle Ages (adjective)
relating to or belonging to the Middle Ages
as if belonging to the Middle Ages; old-fashioned and unenlightened
characteristic of the time of chivalry and knighthood in the Middle Ages