silver age vs time period

silver age and time period both are nouns.

Word	Noun	Adjective	Verb	Adverb
silver age	Yes	No	No	No
time period	Yes	No	No	No

As nouns, time period is a hypernym of silver age; that is, time period is a word with a broader meaning than silver age:

silver age: (classical mythology) the second age of the world, characterized by opulence and irreligion; by extension, a period secondary in achievement to a golden age
time period: an amount of time

Other hypernyms of silver age include period, period of time.

silver age (noun)	time period (noun)
(classical mythology) the second age of the world, characterized by opulence and irreligion; by extension, a period secondary in achievement to a golden age	an amount of time