Source : Webster's Revised Unabridged Dictionary (1913)

Duplicate \Du"pli*cate\, v. t. [imp. & p. p. {Duplicated}; p.
   pr. & vb. n. {Duplicating}.]
   1. To double; to fold; to render double.

   2. To make a duplicate of (something); to make a copy or
      transcript of. --Glanvill.

   3. (Biol.) To divide into two by natural growth or
      spontaneous action; as, infusoria duplicate themselves.