over (and done) with
used about something unpleasant

[TahlilGaran] Dictionary of Contemporary English ▲

over with
over (and done) with
finished or completed.
I had my wisdom tooth out yesterday morning, so that's over and done with.

He skipped to the end of the chapter just to get it over with.

Usage notes: usually refers to something bad or unpleasant

[TahlilGaran] English Idioms Dictionary ▲

over with
to be at the end of something, to be finished with
When the game on television is over with we can eat dinner.

[TahlilGaran] English Idioms Dictionary ▲

over with
over with¹ prep. At the end of; finished with; through with.
They were over with the meeting by ten o'clock.
By Saturday Mary will be over with the measles.
over with² adj., informal At an end; finished.
John knew his mother would scold him for losing the money, and he wanted to get it over with.
After the hard test, Jerry said, "I'm glad that's over with!"

[TahlilGaran] English Idioms Dictionary ▲