Adolescence is the period of psychological and social transition between childhood and adulthood (gender-specific, manhood, or womanhood). Someone in Adolescence is called a Teenager. As a transitional stage of human development it represents the period of time during which a juvenile matures into adulthood.

Biological development (that is, puberty) and psychosocial development , however clearer boundaries relate to physical development.

"Adolescence" is a cultural and social phenomenon and therefore its endpoints are not easily tied to physical milestones. The word derives from the Latin verb adoare meaning "to grow up." The time is identified with dramatic changes in the body, along with developments in a person's psychology and academic career. In the onset of adolescence, children usually complete elementary school and enter secondary education, such as middle school or high school. A person between early childhood and the teenage years is sometimes referred to as a pre-teen or tween .