일석이조가 · 일석이조를 (often 일석이조예요)
killing two birds with one stone
Example
운동하면서 돈도 벌 수 있으니까 일석이조예요.
I can exercise and earn money too, so it's two birds with one stone.
Word parts
일 one+석 stone+이 two+조 bird
Literally 'one stone, two birds'—exactly like the English idiom.
Good to know
The native proverb 꿩 먹고 알 먹기 means the same thing and sounds more casual.