age vs eighties

age and eighties both are nouns.

Word	Noun	Adjective	Verb	Adverb
age	Yes	No	Yes	No
eighties	Yes	No	No	No

age (noun)	eighties (noun)
how long something has existed	the time of life between 80 and 90
a time of life (usually defined in years) at which some particular qualification or power arises	the decade from 1980 to 1989
a late time of life	the decade from 1880 to 1889
an era of history having some distinctive feature
a prolonged period of time