call it a day

Related to call it a day: call it a night

call it a day

To stop working, either at one's job or on a particular task, for the rest of the day. When we still couldn't find the source of the discrepancy, we decided to call it a day and revisit it tomorrow. This package is the last one. Once we get this shipped, we can call it a day.
See also: call
Farlex Dictionary of Idioms.

call it a day

to quit work and go home; to say that a day's work has been completed. I'm tired. Let's call it a day. The boss was mad because Tom called it a day at noon and went home.
See also: call
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

call it a day

Stop a particular activity for the rest of the day, as in It's past five o'clock so let's call it a day. Similarly, call it a night means "to stop something for the rest of the night," as in One more hand of bridge and then let's call it a night. The original phrase was call it half a day, first recorded in 1838, which referred to leaving one's place of employment before the work day was over. The first recorded use of call it a day was in 1919, and of call it a night in 1938. Also see call it quits.
See also: call
The American Heritage® Dictionary of Idioms by Christine Ammer.

call it a day

COMMON
1. If you call it a day, you decide to stop doing something you have been doing that day. I searched for hours but I had to call it a day when darkness fell. Note: In the evening, people sometimes say that they are going to call it a night. Tomorrow is going to be busy, so let's call it a night.
2. If someone calls it a day, they retire from their job. It's no secret I want his job when he calls it a day. He's finally decided to call it a day and retire as manager.
See also: call
Collins COBUILD Idioms Dictionary, 3rd ed.

call it a day

decide or agree to stop doing something, either temporarily or permanently.
This expression comes from the idea of having done a day's work; in the mid 19th century, the form was call it half a day .
See also: call
Farlex Partner Idioms Dictionary

call it a ˈday

(informal) decide to stop doing something, especially something you have been doing for a long time: We’d painted half the room and were feeling a bit tired so we decided to call it a day.
See also: call
Farlex Partner Idioms Dictionary

call it a day

Informal
To stop what one has been doing, for the remainder of the day or at least for the present.
See also: call
American Heritage® Dictionary of the English Language, Fifth Edition.

call it a day, to

To stop work for the time being. The phrase implies that a full day’s work has been done, whether or not the clock so indicates. Indeed, J. C. Neal in Charcoal Sketches (1838) spelled this out: “I’ve a great mind to knock off and call it half a day.”
See also: call
The Dictionary of Clichés by Christine Ammer
See also:
  • call it a day, to
  • Time to call it a day
  • (it's) time to call it a day
  • (it's) time to call it a night
  • Time to call it a night
  • a full-time job
  • let's call it a day
  • be remembered as (something)
  • be remembered as/for something
  • be remembered for (something)