call it a day

verb3

1. •
   To cease an activity.

   • We have been at this for hours; let’s call it a day and come back tomorrow when we are fresh.
2. •
   To retire.

   • After suffering massive losses for three years in a row, the boss decided to call it a day, and sold his company.
3. •
   To end a period of activity, either because it is unsuccessful or because enough has been done.

   • After he was reprimanded for slacking on the job, they decided to call it a day and fire Allen.