Question: what is the meaning of the idiomatic expression call it a day?
Answer: (idiomatic) To retire. After suffering massive losses for three years in a row, the boss decided to call it a day, and sold his company. (idiomatic) To cease the activity for the day. [ from 1919] quotations ▼ We have been at this for hours; let's call it a day and come back tomorrow when we are fresh.