The Collaborative International Dictionary of English v.0.48:

Zoomorphism \Zo`o*mor"phism\, n.
   1. The transformation of men into beasts. [R.] --Smart.
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   2. The quality of representing or using animal forms; as,
      zoomorphism in ornament.
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   3. The representation of God, or of gods, in the form, or
      with the attributes, of the lower animals.
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            To avoid the error of anthropomorphism, we fall into
            the vastly greater, and more absurd, error of
            zoomorphism.                          --Mivart.
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WordNet (r) 3.0 (2006):

zoomorphism
    n 1: the attribution of animal forms or qualities to a god