The point at which you are fully grown is an example of when you achieve maturity.
Showing common sense and making adult decisions is an example of maturity.
A fruit that is fully-ripe is an example of a fruit that has reached maturity.
A bank note that is due for payment is an example of a note that has reached maturity.
- A being full-grown, ripe, or fully developed.
- A being perfect, complete, or ready.
Some foods and drinks, like wine, only reach their full taste at maturity, which literally comes at a price.