mature

adjective

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

  "She is quite mature for her age."

• Brought to a state of complete readiness.

  "a mature plan"

• Profound; careful.

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

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

  "mature content"