What does "clue" mean?

Clue: That which guides or directs one in anything of a doubtful or intricate nature; that which gives a hint in the solution of a mystery. The clew, without which it was perilous to enter the vast and intricate maze of countinental politics, was in his hands. Macaulay.

Additional senses

  1. 2.(Naut.) (a.) A lower corner of a square sail, or the after corner of a fore- and-aft sail. (b.) A loop and thimbles at the corner of a sail. (c.) A combination of lines or nettles by which a hammock is suspended. Clew garnet (Naut.), one of the ropes by which the clews of the courses of square-rigged vessels are drawn up to the lower yards. -- Clew line (Naut.), a rope by which a clew of one of the smaller square sails, as topsail, topgallant sail, or royal, is run up to its yard. -- Clew-line block (Naut.), The block through which a clew line reeves. See Illust. of Block.
  2. 3.A ball of thread; a thread or other means of guidance. Same as Clew. You have wound a goodly clue. Shak. This clue once found unravels all the rest. Pope. Serve as clues to guide us into further knowledge. Locke.

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