age out

The phrasal verb preposition out is analogous to run out. Usage was likely spread by the Boy Scouts of America, where it is largely used in the first sense to mean turning eighteen and becoming ineligible for the youth program.

age out (third-person singular simple present ages out, present participle aging out or ageing out, simple past and past participle aged out)

1. (intransitive) To become too old for an activity, program or institution; to become too mature for a behavior.

   When foster kids age out, it is important that the state provides them with support.

   • 2021 February 9, Christina Newland, “Is Tom Hanks part of a dying breed of genuine movie stars?”, in BBC‎:

     But they [movie stars] do seem to be aging out. There's Leonardo DiCaprio at 46, Johnson, at 48 years old, and Brad Pitt, at 57; Tom Cruise, at 58.

2. (euphemistic, politics) To die or retire.

   The party's chances in the coming election looked grim as a large portion of their voters were going to age out.

• over the hill

• outage