Age of Fishes vs Devonian

Age of Fishes and Devonian both are nouns.

Word	Noun	Adjective	Verb	Adverb
Age of Fishes	Yes	No	No	No
Devonian	Yes	No	No	No

As nouns, Age of Fishes and Devonian are synonyms defined as:

Age of Fishes and Devonian: the period from 405 million to 345 million years ago; characterized by preponderance of fishes and appearance of amphibians and ammonites

Other synonyms of Age of Fishes include Devonian period.

Age of Fishes (noun)	Devonian (noun)
the period from 405 million to 345 million years ago; characterized by preponderance of fishes and appearance of amphibians and ammonites	the period from 405 million to 345 million years ago; characterized by preponderance of fishes and appearance of amphibians and ammonites