AGE, in the most general sense of the term, denotes the duration of any substance, animate or inanimate; and is applied either to the whole period of its existence, or to that portion of it which precedes the time to which the description of it refers. In this sense it is used to signify either the whole natural duration of the LIFE of man, or any interval of it that has elapsed before the period of which we speak. When age is understood of a certain portion of the life of man, its whole duration is divided into four different ages, viz. infancy, youth, manhood, and old age: the first extending to the fourteenth year; the second, denominated youth, adolescence, or the age of puberty, commencing at fourteen, and terminating at about twenty-five; manhood, or the virile age, concluding at fifty; and the last ending at the close of life. Some divide the first period into infancy and childhood; and the last likewise into two stages, calling that which succeeds the age of seventy-five, decrepit old age. Age is applicable to the duration of things inanimate or factitious; and in this use of the term we speak of the age of a house, of a country, of a state or kingdom, &c. AGE, in _chronology_, is used for a century, or a period of one hundred years: in which sense it is the same with _seculum_, and differs from _generation_. It is also used in speaking of the times past since the creation of the world. The several ages of the world may be reduced to three grand epochas, viz. the age of the law of nature, called by the Jews the void age, from Adam to Moses. The age of the Jewish law, from Moses to Christ, called by the Jews the present age. And the age of grace, from Christ to the present year. The Jews call the third age, the age to come, or the future age; denoting by it the time from the advent of the Messiah to the end of the world. The Romans distinguished the time that preceded them into three ages: the obscure or uncertain age, which reached down as low as Ogyges king of Attica, in whose reign the deluge happened in Greece; the fabulous or heroic age, which ended at the first olympiad; and the historical age, which commenced at the building of Rome. Among the poets, the four ages of the world are, the golden, the silver, the brazen, and the iron age. Age is sometimes used among the ancient poets in the same sense as _generation_, or a period of thirty years. Thus Nestor is said to have lived three ages, when he was ninety years old.