Senses
一日不见，如隔三秋/ 一日不見，如隔三秋 one day apart seems like three years
One day without seeing each other feels like three years have passed; used to describe missing someone very much.
一日不见，如隔三秋/ 一日不見，如隔三秋 one day feels like three years
one day away from a loved one feels like three autumns; missing someone dearly