The Collaborative International Dictionary of English v.0.48:

Homomorphism \Ho`mo*mor"phism\, n. [See Homomorphous.]
   1. (Biol.) Same as Homomorphy.
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   2. (Bot.) The possession, in one species of plants, of only
      one kind of flowers; -- opposed to heteromorphism,
      dimorphism, and trimorphism.
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   3. (Zool.) The possession of but one kind of larv[ae] or
      young, as in most insects.
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