유구무언이 · 유구무언을
having nothing to say for oneself
Example
모두 제 실수라서 정말 유구무언입니다.
It's all my fault, so I really have nothing to say for myself.
Word parts
유 have+구 mouth+무 without+언 words
Literally 'having a mouth but no words'.
Good to know
Used in apologies to humbly admit fault, especially in formal settings.
Related words