I have not yet got the clue: to give a clue, i.e. a hint. A clue is a ball of thread (Ang-Saxon, cleowen) The only mode of finding the way out of the Cretan labyrinth was by a skein of thread, which, being laid along the proper route, indicated the right path.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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