Mature

adjective

1. Fully developed; grown up in terms of physical appearance, behaviour or thinking; ripe.

   "She is quite mature for her age."

2. Brought to a state of complete readiness.

   "a mature plan"

3. Profound; careful.

   "The headmaster decided to expel the boy after a mature consideration."

4. Come to, or in a state of, completed suppuration.
5. Suitable for adults only, due to sexual themes, violence, etc.

   "mature content"