turn of the century vs age

turn of the century and age both are nouns.

Word	Noun	Adjective	Verb	Adverb
turn of the century	Yes	No	No	No
age	Yes	No	Yes	No

As nouns, age is a hypernym of turn of the century; that is, age is a word with a broader meaning than turn of the century:

turn of the century: the period from about ten years before to ten years after a new century
age: an era of history having some distinctive feature

Other hypernyms of turn of the century include historic period.

turn of the century (noun)	age (noun)
the period from about ten years before to ten years after a new century	how long something has existed
	a time of life (usually defined in years) at which some particular qualification or power arises
	a late time of life
	an era of history having some distinctive feature
	a prolonged period of time