3 Words and More in Running Man Ep. 306(수상한 R 구조대, Strange Rescue Team)
전성기 means the heyday, prime, best days, glory days, or golden age.
전성기가 지났지만 여전히 좋은 기량을 보여 주고 있다.
His golden age has been passed, but he still shows great skills.
두번째 전성기가 찾아 왔다.
The second golden age has arrived.
For some reason, Koreans like to talk courage or guts with liver in our body. 간이 떨어지다 means when you are startled. 간이 붓다 is used when someone shows unreasonable or reckless courage.
간이 크다 is used when someone is trying something really dangerous. Before the screenshot, 광수 hit the leg of 종국.
참 간도 크다. 어떻게 그런 짓을 할 생각을 했어.
You are so reckless. How did you imagine to do that?
그냥 하던대로 한 건데, 다들 간이 크다고 하더라고.
I did as I always do, but they say I did something bold.
The basic meaning of this word is side effect. As we all know, this meaning came from the medical field.
Sometimes, this word is used for some unexpected (bad) result. In the screenshot above, we didn't expect that he will have a cramp. That's why this phrase is used.
연승에도 부작용이 있어.
There is also a side effect to continuous win.
어떤 부작용이 있을 줄 아는 데도 그렇게 한 거야?
You knew the side effect. But you did so?