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clue; lead; key; trail; scent; track
handhold; hold
事件解決の手がかりとなる証拠が現場で発見された。
Evidence that could serve as a clue to solving the case was found at the scene.
手がかりが少なく、捜査は難航を極めている。
With few leads, the investigation is proving extremely difficult.
古文書が文明の起源を探る手がかりになるかもしれない。
Ancient documents might provide clues for tracing the origins of civilization.