also: ねんげつ
months and years; time; passage of time
Refers to the flow or accumulation of time, often with a sense of duration or the weight of passing years. Common in expressions like 年月が経つ (time passes).
年月が経つのは早いものだ。
How quickly the months and years go by.
This technology has developed over many years.
That research took many years to complete.
Many years have passed since that accident.
He built the castle over many long years.