(transitive or intransitive) To become too old for an activity, program or institution; to become too mature for a behavior.
Example: Used other than as an idiom: see age,â€Ž out.
The liquor has a foul taste at this point, but that's why we age it; those bitter notes will age out of the product by the time it is ready to sell.
When foster kids age out, it is important that the state provides them with support.
Most kids age out of that by the time they're ten or eleven years old.