Clean up
(PW) make a big profit
Since he started his new business, he’s really cleaning up.
(MW)
Main Entry: 1clean·up
Pronunciation: \ˈklēn-ˌəp\
Function: noun
Date: 1872
1 : an act or instance of cleaning
2 : an exceptionally large profit : killing
(free)
clean up
1. To make clean or orderly.
2. To make oneself clean, neat, or presentable.
3. To dispose of; settle: cleaned up the unpaid bills.
4. Slang To make a large profit, often in a short period of time: cleaned up during the bull market.