The Collaborative International Dictionary of English v.0.48:

Stereotype \Ste"re*o*type\, n. [Stereo- + -type: cf. F.
   st['e]r['e]otype.]
   1. A plate forming an exact faximile of a page of type or of
      an engraving, used in printing books, etc.; specifically,
      a plate with type-metal face, used for printing.
      [1913 Webster]

   Note: A stereotype, or stereotypr plate, is made by setting
         movable type as for ordinary printing; from these a
         cast is taken in plaster of Paris, paper pulp, or the
         like, and upon this cast melted type metal is poured,
         which, when hardened, makes a solid page or column,
         from which the impression is taken as from type.
         [1913 Webster]

   2. The art or process of making such plates, or of executing
      work by means of them.
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   Stereotype block, a block, usually of wood, to which a
      stereotype plate is attached while being used in printing.
      [1913 Webster]