to stop what you are doing because you do not want to do any more or think you have done enough

I'm getting a bit tired now - let's call it a day. 我有些累了——收工吧。

After 14 years living and working in this country, she thinks it's time to call it a day. 在这个国家生活和工作了14年后，她认为是结束的时候了。