Adolescence

n. age of puberty; youth

Adolescence is a transitional stage of human development that occurs between childhood and adulthood. Adolescent humans go through puberty, the process of sexual maturation. Teenagers (ages 13-19) are usually adolescent, though in some individuals, puberty may extend a few years beyond the teenage years, and in some individuals, puberty begins in the pre-teen years.
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Noun
1. the time period between the beginning of puberty and adulthood
(hypernym) time of life
(part-holonym) youth
(part-meronym) genital stage, genital phase
(derivation) adolesce
2. in the state that someone is in between puberty and adulthood
(hypernym) immaturity, immatureness
(derivation) adolesce

n. adolescence, teenage years; boyhood, teens

(n.)
The state of growing up from childhood to manhood or womanhood; youth, or the period of life between puberty and maturity, generally considered to be, in the male sex, from fourteen to twenty-one. Sometimes used with reference to the lower animals.