(idiomatic) A period of happiness, peace, prosperity, and/or great progress. / (mythology) The Golden Age.

Belonging in the Stone Age.

the time of the Industrial Revolution

(historical) A historical period of great accomplishment in a field or a society, usually following, and not quite as favorable as, a golden age, and not unfavorable as an iron age.

The chronological age of individuals of the same maturity as the person in question.

(idiomatic) A time period of years or more.

Alternative letter-case form of space age

The period from the about the time of the launch of Sputnik in 1957 to the present day, during which people ventured into space. / (attributive) Redolent of the space age; appearing futuristic or modern.

Being of an age during which attendance at school is customary.

Synonym of prehistory: the era before written records.