adjective / noun
juvenile
JOO-vuh-nul/ˈdʒuːvənl/
Belonging to an early stage before adulthood.
Her juvenile reaction to losing the game includes sticking out her tongue.

Etymology
The pieces express ‘belonging to youth.’ That can neutrally describe young people or, when applied to behavior, judge it as immature rather than merely youthful.
In context
offenders and their families the family and new Services Bureau came into being in 1974 specifically to meet the needs of young people who were being placed inappropriately in the juvenile justice system
More examples
- The program offers job training to juveniles.
- This juvenile tree has not yet produced fruit.
- The shelter houses adult cats and juveniles in separate rooms.
Forms
juvenile · juveniles
Similar words
- young
- More general and less formal; does not necessarily mean immature.
- adolescent
- Specifically describes the stage between childhood and adulthood.
- immature
- Emphasizes incomplete development rather than simply being young.