be over the hill
(also be past it) to be too old to do something

[TahlilGaran] Dictionary of Contemporary English ▲

old having lived for a long time:
an old man
I’m too old to learn a new language.
elderly a polite word for old:
an elderly lady
a home for the elderly (=elderly people)
If you are elderly, you may be eligible for financial assistance.
aging (also ageing British English) [only before noun] becoming old:
an ageing rock star
the problems of an ageing population
aged /ˈeɪdʒəd, ˈeɪdʒɪd/ [only before noun] written aged relatives are very old:
aged parents
She had to look after her aged aunt.
elder brother/sister especially British English [only before noun] an older brother or sister. Elder sounds more formal than older:
I have two elder brothers.
ancient [not usually before noun] informal very old – used humorously:
I’ll be 30 next year – it sounds really ancient!
be getting on (in years) informal to be fairly old:
He’s 60 now, so he’s getting on a bit.
be over the hill (also be past it British English) informal to be too old to do something:
Everyone thinks you’re past it when you get to 40.
geriatric [only before noun] relating to medical care and treatment for old people:
a geriatric hospital
geriatric patients
antique antique furniture, clocks, jewellery etc are old and often valuable:
an antique writing desk
age-old used about traditions, problems, or situations that have existed for a very long time:
the age-old tradition of morris dancing
the age-old prejudice against women in positions of power
the age-old problem of nationalism
age-old hatreds between religious groups

[TahlilGaran] English Thesaurus ▲

over the hill
no longer able to do something at an acceptable level because of age.
Some judges who are 75 may be over the hill, but others still have energy galore.

[TahlilGaran] English Idioms Dictionary ▲

over the hill
to be past one's prime, to be unable to function as one used to
I thought that my friend was over the hill and should not be working at all.

[TahlilGaran] English Idioms Dictionary ▲

over the hill
adj., informal Past one's prime; unable to function as one used to; senile.
Poor Mr. Jones is sure not like he used to be; well, he's over the hill.

[TahlilGaran] English Idioms Dictionary ▲