in (one's) day
in (one's) day
in somebody’s day/time
1 when somebody was most successful, famous, etc: He had, in his day, been one of the greatest opera singers in the world.
2 at the time when somebody was alive; when somebody was young: In my grandmother’s time, women were expected to stay at home and look after the children. ♢ In my day, nobody would have spoken to the boss like that.