If I get paid properly I don't mind working overtime.
While I was working overtime, the wood fell and I narrowly escaped death.
After working overtime I went to an Italian restaurant alone. I felt pretty lonely lol.
The remainder of time that you work at the ol' business is extra time that you're working (above the normal work hours). This is overtime!
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.