The Collaborative International Dictionary of English v.0.48:

Archetype \Ar"che*type\ ([aum]r"k[-e]*t[imac]p), n. [L.
   archetypum, Gr. 'arche`typon, fr. 'arche`typos stamped first
   and as model; 'arche = 'archi + ty`pos stamp, figure,
   pattern, ty`ptein to strike: cf. F. arch['e]type. See
   Arch-, pref.]
   1. The original pattern or model of a work; or the model from
      which a thing is made or formed.
      [1913 Webster]

            The House of Commons, the archetype of all the
            representative assemblies which now meet.
                                                  --Macaulay.
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            Types and shadows of that glorious archetype that
            was to come into the world.           --South.
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   2. (Coinage) The standard weight or coin by which others are
      adjusted.
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   3. (Biol.) The plan or fundamental structure on which a
      natural group of animals or plants or their systems of
      organs are assumed to have been constructed; as, the
      vertebrate archetype.
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WordNet (r) 3.0 (2006):

archetype
    n 1: something that serves as a model or a basis for making
         copies; "this painting is a copy of the original" [syn:
         original, archetype, pilot]