hoary
[adjective]
Synonyms: ancient, aged, age-old, antediluvian, antique, Noachian, old, timeworn, venerable

[TahlilGaran] English Synonym Dictionary ▲

hoar‧y /ˈhɔːri/ adjective
[Date: 1500-1600; Origin: hoar; ⇒ hoarfrost]

1. [usually before noun] a hoary joke, remark etc is so well known that people no longer find it amusing or interesting:
Not that hoary old chestnut (=old idea, joke, remark etc) again.

2. old-fashioned grey or white in colour, especially through age

[TahlilGaran] Dictionary of Contemporary English ▲