단서가 · 단서를
clue, lead
Example
경찰은 사건의 중요한 단서를 찾았어요.
The police found an important clue in the case.
Word parts
단 end+서 thread
Literally 'end of a thread': pull it and the story unravels.
Good to know
Homonym: a different 단서 means 'proviso', as in 단서를 달다 'to attach a condition', common in formal writing.
Related words