expression, noun-modifying (irregular)
Prenominal phrase used to describe a person who is advanced in years. Often softer than 年寄り.
年のいった男性が公園のベンチに座っていた。
An elderly man was sitting on a bench in the park.
彼は年のいった犬を引き取った。
He adopted an older dog.
Phrase composed of 年 (year/age) + の (possessive particle) + いった (past tense of 行く, here meaning 'advanced'). Literally 'years have advanced', used attributively.