What does "duplicate" mean?

Duplicate: That which exactly resembles or corresponds to something else; another, correspondent to the first; hence, a copy; a transcript; a counterpart. I send a duplicate both of it and my last dispatch. Sir W. Temple.

Additional senses

  1. 2.(Law) An original instrument repeated; a document which is the same as another in all essential particulars, and differing from a mere copy in having all the validity of an original. Burrill.
  2. 3.To double; to fold; to render double.
  3. 4.To make a duplicate of (something); to make a copy or transcript of. Glanvill.
  4. 5.(Biol.) To divide into two by natural growth or spontaneous action; as, infusoria duplicate themselves.

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