뭘까

what could it be?, what might it be?

→ 뭐+일까
pronoun · informal Uncommon #10,206
what could it be?, what might it be? A wondering or speculative form of “what is it?”
KO: 저 상자 안에는 뭘까?
EN: What could be inside that box?

소년이 비참하게 죽게 된 원인이 뭘까?

What was the cause of the boy's miserable death?

— 하얀 리본 (2009)

이게 대체 뭘까?

What on earth is this?

— 크리에이터 (2023)

이게 다 뭘까?

What is all this?

— 알.이.씨 (2007)

원인이 뭘까?

What is the cause?

— 스테이션 7 (2017)

도대체 뭘까?

What on earth is it?

— 국보 (2025)

그래, 이게 뭘까?

Yeah, what is this?

— 아마코드 (1973)