noun / adjective
adolescent
ad-uh-LES-unt/ˌædəˈlesnt/
A young person, or relating to the stage between childhood and adulthood.
The adolescent carries a backpack and notebook.

Etymology
The pieces describe growing toward maturity. The participial ending presents this as an ongoing process, and the Latin description “growing, youthful” became a noun for a young person undergoing that development.
In context
trapped in an adolescent's body
More examples
- Several adolescents joined the club.
- She studied adolescent development.
- He remembered his adolescent years.
Forms
adolescent · adolescents
adolescence noun — the stage between childhood and adulthood