noun
ten years is a long time; things change so much in ten years that it feels like a different era
Proverbial yojijukugo expressing that a decade brings such great change that the past seems distant. Often used when reflecting on how much has changed.
十年一昔と言うが、十年前のスマートフォンはもう懐かしい。
They say ten years is a long time, and smartphones from ten years ago already feel nostalgic.
この街も十年一昔で、ずいぶん景色が変わった。
This town has changed so much in ten years that it feels like a different place.