past one's prime

past (someone's or something's) prime

No longer in an ideal state or condition. Many gymnasts are past their prime when they are only teenagers. This computer is so slow that it's definitely past its prime.
See also: past, prime
Farlex Dictionary of Idioms.

past one's prime

Beyond the peak of one's powers, as in Jean still plays tennis but at 79 she's obviously past her prime. Also see the synonym over the hill; prime of life.
See also: past, prime
The American Heritage® Dictionary of Idioms by Christine Ammer.
See also:
  • past (someone's or something's) prime
  • past prime
  • be past (someone's or something's) best
  • be past your/its best
  • model
  • be a/the model of (something)
  • suit (one) to a T
  • suit (one) to a tee
  • suit to a T
  • ain't it the truth
References in periodicals archive
Baby boomers have traded in the traditional view of aging as being past one's prime for actively going after their "bucket list" goals.
A man's guide to healthy aging; stay smart, strong, and active
In Music City any hint of being past one's prime spells trouble.
Don't call it a comeback: Reba McEntire may be down a TV show, but with a little help from her friends, she's back on top of her country game
Not to mention the pressure to keep working until the standard Silicon Valley retirement age of thirty, which may seem young to some readers, but is still well past one's prime skateboarding years.
Fondling My Stock Options