뭐였더라

what was it again?, what was ... again?

→ 뭐+였더라
뭐 well, you know, like + 였 Past tense + 더라 Retrospective past
pronoun · informal Rare #26,608
what was it again?, what was ... again? Used when trying to remember something.
KO: 그 사람 이름이 뭐였더라?
EN: What was that person's name again?

질문이 뭐였더라

What was the question again?

— A Moment to Remember (2004)

이름이 뭐였더라

What was your name again?

— 산딸기 (1957)

그는 시인 이었지 최고의 시가 뭐였더라?

He was a poet. What was his best poem?

— 8과 1/2 (1963)

그 녀석의 이름 뭐였더라

What was that guy's name again?

— 너의 이름은. (2016)