3 Words in Running Man 331(Bad Santa)
This word originally came from 경상 dialect. In 경상도, 아재 means 아저씨, middle-aged man, mister, uncle.
When it is used in TV shows or between common Koreans, it usually means old-fashioned.
Examples are 아재 개그(old-fashioned humor), 아재 스타일(old-fashioned fashion/style), 아재 버거(hamburger that has a lot of good ingredients for 아재s), etc.
아재 개그 좀 그만해. 재미 없어.
Stop those old humors. They aren't funny.
우리랑 놀더니 완전히 아재 다 됐네.
You hang out with us and became like an old school.
This word is a shortened version of "열심히 일하다", working hard.
Interestingly, this word is sometimes used when "열심히 일하다" cannot be used like "미모가 열일 중", meaning that "her beauty is amazing".
It is usually used like 열일하다 or 열일 중.
그는 올해도 열일이다.
He's working hard this year, too.
오늘도 열일 중.
I'm working hard today.
When someone tries to take credit for nothing or what he didn't do, something really trivial, it is called 생색을 내다 in Korean.
Before the moment in screenshot, 재석 said that he would let 광수 pass the penalty. Actually, they agreed that the one whose nametag doesn't show up would get it. He sounds like he did something really great for him, but it is what 광수 should natually take. 재석 took credit for nothing, so he's 생색을 내고 있다.
왜 그렇게 생색이야? 그냥 주지.
Why are you taking that much credit? Just give it.
생색 내지 않기 위해 노력했다.
I tried my best not to take credit for it.