/ ˈpeɪbæk; NAmE / noun [ C , U ]
1.
the money that you receive back on money that you have invested (especially when this is equal to the amount that you invested to start with); the time that it takes to get your money back :
a 10-year payback
2.
the advantage or reward that sb receives for sth they have done; the act of paying sth back :
His victory was seen as payback for all the hard work he'd put in during training.
( informal )
It's payback time ! (= a person will have to suffer for what they have done)