the state of growing youth, or that period of a person's age commencing from his infancy and terminating at his full stature or manhood. The word is formed of the Latin adolescere, to grow. The state of adolescence lasts so long as the fibres continue to grow either in magnitude or firmness. The fibres being arrived at the degree of firmness and tension sufficient to sustain the parts, no longer yield or give way to the efforts of the nutritious matter to extend them; so that their further accretion is stopped, from the very law of their nutrition. Adolescence is commonly computed to be between 15 and 25, or even 30 years of age; though in different constitutions its terms are very different. The Romans usually reckoned it from 12 to 25 in boys, and to 21 in girls, &c. And yet, among their writers, juvenis and adolescentes are frequently used indifferently for any person under 45 years.