A work which is hard, repetitive and boring.
I really hate it that I have to do all the dirty work while my colleagues take long vacations.
=a long time
He's been living in that small town for donkey's years.
work like a horse
work very hard
I have an important deadline coming up, so I've been working like a horse.
a long day
It was a long day.
I've had a long day.。