month of Sundays vs age

month of Sundays and age both are nouns.

Word	Noun	Adjective	Verb	Adverb
month of Sundays	Yes	No	No	No
age	Yes	No	Yes	No

As nouns, age is a hypernym of month of Sundays; that is, age is a word with a broader meaning than month of Sundays:

Other hypernyms of month of Sundays include long time, years.

month of Sundays (noun)	age (noun)
a time perceived as long	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